Hi everyone! This is my first post for a long time, I have only done a bit of VB6 programming and VBA in Excel in spreadsheets for my work as an engineer, so please excuse my inexperience!
I had a graduate engineer, left a long time ago, write a spreadsheet with VBA which I have modified for 64-bit compatibility but have now hit a brick wall as it calls a DLL, which they also wrote. I have the original files used to compile the DLL, but no idea which file I need to launch or what program I need to edit them to 64-bit and compile again.

Files in main folder:
Name: Main Folder.jpg Views: 159 Size: 23.2 KB

Files in Release folder:
Name: Release Folder.jpg Views: 144 Size: 17.2 KB

Any advice or help would be gratefully appreciated as I feel completely out of my depth, I struggled to make the VBA code 64-bit compliant.

Thanks for reading.