VB .Net-System.ArgumentException: 'Argument 'Length' must be greater or equal to zero

[Rocky48]

I am trying to use some code which is a Class, for producing PDF files. (GNU Licence)
IT seems that the code has several errors.
There are only a few basic fonts, so I have created another font file in the style of an existing font.
The helveticab font was existing and is shown below.

key =helveticaB
cw = chr(0) , 278,chr(1) , 278,chr(2) , 278,chr(3) , 278,chr(4) , 278,chr(5) , 278,chr(6) , 278,chr(7) , 278,chr(8) , 278,chr(9) , 278,chr(10) , 278,chr(11) , 278,chr(12) , 278,chr(13) , 278,chr(14) , 278,chr(15) , 278,chr(16) , 278,chr(17) , 278,chr(18) , 278,chr(19) , 278,chr(20) , 278,chr(21) , 278,chr(22) , 278,chr(23) , 278,chr(24) , 278,chr(25) , 278,chr(26) , 278,chr(27) , 278,chr(28) , 278,chr(29) , 278,chr(30) , 278,chr(31) , 278,chr(32)  , 278,! , 333, chr(34), 474,# , 556,$ , 556,% , 889,& , 722,' , 238,( , 333,) , 333,* , 389,+ , 584,chr(44) , 278,- , 333,. , 278,/ , 278,0 , 556,1 , 556,2 , 556,3 , 556,4 , 556,5 , 556,6 , 556,7 , 556,8 , 556,9 , 556,: , 333,; , 333,< , 584,= , 584,> , 584,? , 611,@ , 975,A , 722,B , 722,C , 722,D , 722,E , 667,F , 611,G , 778,H , 722,I , 278,J , 556,K , 722,L , 611,M , 833,N , 722,O , 778,P , 667,Q , 778,R , 722,S , 667,T , 611,U , 722,V , 667,W , 944,X , 667,Y , 667,Z , 611,[ , 333,\ , 278,] , 333,^ , 584,_ , 556,` , 333,a , 556,b , 611,c , 556,d , 611,e , 556,f , 333,g , 611,h , 611,i , 278,j , 278,k , 556,l , 278,m , 889,n , 611,o , 611,p , 611,q , 611,r , 389,s , 556,t , 333,u , 611,v , 556,w , 778,x , 556,y , 556,z , 500,{ , 389,| , 280,} , 389,~ , 584,chr(127) , 350,chr(128) , 556,chr(129) , 350,chr(130) , 278,chr(131) , 556,chr(132) , 500,chr(133) , 1000,chr(134) , 556,chr(135) , 556,chr(136) , 333,chr(137) , 1000,chr(138) , 667,chr(139) , 333,chr(140) , 1000,chr(141) , 350,chr(142) , 611,chr(143) , 350,chr(144) , 350,chr(145) , 278,chr(146) , 278,chr(147) , 500,chr(148) , 500,chr(149) , 350,chr(150) , 556,chr(151) , 1000,chr(152) , 333,chr(153) , 1000,chr(154) , 556,chr(155) , 333,chr(156) , 944,chr(157) , 350,chr(158) , 500,chr(159) , 667,chr(160) , 278,chr(161) , 333,chr(162) , 556,chr(163) , 556,chr(164) , 556,chr(165) , 556,chr(166) , 280,chr(167) , 556,chr(168) , 333,chr(169) , 737,chr(170) , 370,chr(171) , 556,chr(172) , 584,chr(173) , 333,chr(174) , 737,chr(175) , 333,chr(176) , 400,chr(177) , 584,chr(178) , 333,chr(179) , 333,chr(180) , 333,chr(181) , 611,chr(182) , 556,chr(183) , 278,chr(184) , 333,chr(185) , 333,chr(186) , 365,chr(187) , 556,chr(188) , 834,chr(189) , 834,chr(190) , 834,chr(191) , 611,chr(192) , 722,chr(193) , 722,chr(194) , 722,chr(195) , 722,chr(196) , 722,chr(197) , 722,chr(198) , 1000,chr(199) , 722,chr(200) , 667,chr(201) , 667,chr(202) , 667,chr(203) , 667,chr(204) , 278,chr(205) , 278,chr(206) , 278,chr(207) , 278,chr(208) , 722,chr(209) , 722,chr(210) , 778,chr(211) , 778,chr(212) , 778,chr(213) , 778,chr(214) , 778,chr(215) , 584,chr(216) , 778,chr(217) , 722,chr(218) , 722,chr(219) , 722,chr(220) , 722,chr(221) , 667,chr(222) , 667,chr(223) , 611,chr(224) , 556,chr(225) , 556,chr(226) , 556,chr(227) , 556,chr(228) , 556,chr(229) , 556,chr(230) , 889,chr(231) , 556,chr(232) , 556,chr(233) , 556,chr(234) , 556,chr(235) , 556,chr(236) , 278,chr(237) , 278,chr(238) , 278,chr(239) , 278,chr(240) , 611,chr(241) , 611,chr(242) , 611,chr(243) , 611,chr(244) , 611,chr(245) , 611,chr(246) , 611,chr(247) , 584,chr(248) , 611,chr(249) , 611,chr(250) , 611,chr(251) , 611,chr(252) , 611,chr(253) , 556,chr(254) , 611,chr(255) , 556

Here is a new font file that I have created myself based on the php version that this was adaped from:

key = 'frscript';
cw = chr(0),1000,chr(1),1000,chr(2),1000,chr(3),1000,chr(4),1000,chr(5),1000,chr(6),1000,chr(7),1000,chr(8),1000,chr(9),1000,chr(10),1000,chr(11),1000,chr(12),1000,chr(13),1000,chr(14),1000,chr(15),1000,chr(16),1000,chr(17),1000,chr(18),1000,chr(19),1000,chr(20),1000,chr(21),1000,
	chr(22),1000,chr(23),1000,chr(24),1000,chr(25),1000,chr(26),1000,chr(27),1000,chr(28),1000,chr(29),1000,chr(30),1000,chr(31),1000,' ',250,'!',281,'"',260,'#',615,'$',365,'%',667,'&',646,'\'',135,'(',188,')',188,'*',365,'+',615,
	',',188,'-',188,'.',188,'/',490,'0',365,'1',365,'2',365,'3',365,'4',365,'5',365,'6',365,'7',365,'8',365,'9',365,':',188,';',188,'<',615,'=',615,'>',615,'?',427,'@',917,'A',510,
	'B',677,'C',469,'D',698,'E',521,'F',552,'G',521,'H',802,'I',521,'J',469,'K',813,'L',573,'M',979,'N',875,'O',573,'P',542,'Q',573,'R',740,'S',573,'T',521,'U',740,'V',667,'W',833,
	'X',646,'Y',698,'Z',542,'[',188,'\\',490,']',188,'^',562,'_',500,'`',333,'a',344,'b',333,'c',250,'d',302,'e',260,'f',198,'g',354,'h',354,'i',188,'j',198,'k',375,'l',188,'m',479,
	'n',333,'o',313,'p',344,'q',344,'r',240,'s',260,'t',219,'u',344,'v',271,'w',385,'x',323,'y',344,'z',292,'{',438,'|',479,'}',438,'~',667,chr(127),1000,chr(128),370,chr(129),1000,chr(130),188,chr(131),396,
	chr(132),333,chr(133),1000,chr(134),438,chr(135),438,chr(136),333,chr(137),938,chr(138),573,chr(139),250,chr(140),958,chr(141),1000,chr(142),542,chr(143),1000,chr(144),1000,chr(145),188,chr(146),188,chr(147),333,chr(148),375,chr(149),281,chr(150),365,chr(151),740,chr(152),333,chr(153),906,
	chr(154),260,chr(155),250,chr(156),458,chr(157),1000,chr(158),292,chr(159),698,chr(160),250,chr(161),281,chr(162),365,chr(163),375,chr(164),615,chr(165),563,chr(166),479,chr(167),469,chr(168),333,chr(169),771,chr(170),260,chr(171),385,chr(172),667,chr(173),188,chr(174),760,chr(175),500,
	chr(176),344,chr(177),615,chr(178),240,chr(179),240,chr(180),333,chr(181),458,chr(182),479,chr(183),188,chr(184),333,chr(185),240,chr(186),240,chr(187),385,chr(188),574,chr(189),573,chr(190),574,chr(191),427,chr(192),510,chr(193),510,chr(194),510,chr(195),510,chr(196),510,chr(197),510,
	chr(198),833,chr(199),469,chr(200),521,chr(201),521,chr(202),521,chr(203),521,chr(204),521,chr(205),521,chr(206),521,chr(207),521,chr(208),698,chr(209),875,chr(210),573,chr(211),573,chr(212),573,chr(213),573,chr(214),573,chr(215),615,chr(216),573,chr(217),740,chr(218),740,chr(219),740,
	chr(220),740,chr(221),699,chr(222),574,chr(223),375,chr(224),344,chr(225),344,chr(226),344,chr(227),344,chr(228),344,chr(229),344,chr(230),438,chr(231),250,chr(232),260,chr(233),260,chr(234),260,chr(235),260,chr(236),188,chr(237),188,chr(238),188,chr(239),188,chr(240),302,chr(241),333,
	chr(242),313,chr(243),313,chr(244),313,chr(245),313,chr(246),313,chr(247),615,chr(248),313,chr(249),344,chr(250),344,chr(251),344,chr(252),344,chr(253),344,chr(254),344,chr(255),344)

When I run this code the class code FPDF_net.vb (attached)it reports the above error line 1992.
Cant anyone see why this is happening?