You are probably missing a slash or something.
The easy thing is to do something like:
Get ( DesktopPath ) & Get ( ScriptParameter)
Get ( DocumentsPath ) & Get ( ScriptParameter )
It will figure out the first part of the path that you need.
If only you showed us what is in CALCULATIONS::g_files_path field...
Given the windows calc I expect it starts with a "//". You might... if you want to manually calculate that path... try "///"
This will only work on the local machine... or off a mounted volume.