ML used for matrix computing

I upgraded Matlab to 2007a and my program (enharited) stucks when comes to do Compute (see below).
"Tips": If I activate a (fake/"tester") file between Call MLEvalString("LogRet") and Sheets("Test").Select lines, the program goes on but, of course, I get errors later. If I use "MD" instead of "LR" in Call MLGetMatrix("LR", "B11") line I advance a bit, but I overflow later.

Sub Compute_returns()
' until here I already selected a matrix of data
Call matlabinit
Call MLPutMatrix("MD", Selection)
Call MLEvalString("LogRet")
Sheets("Test").Select
Call MLGetMatrix("LR", "B11")
MatLabRequest
Call Compute
Application.CutCopyMode = False
End Sub

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