After tinkering for two days with Virtual Box and Cameyo I managed do get portable Exel5 work and open any Exel-file via context menu...
(I was not able to do that under Win10(32) VirtualBox (it hung where the Prod.-key had to be entered), so I did it with Win 8.1(64) gererating a clean Win7 prof (32) with VirtualBox. Had some difficulties go get Cameyo and the Excel-Installation files into VirtualBox but eventually it worked)
Everything works fine now under Win10 Prof. 32Bit.
Now I tried to portate the prepared Excel to a different machine which works with Win10 Home 64Bit and get following message:
"Could not execute c:\EXCEL\EXCEL.EXE (Error=216)"
I'm now quite sure (Excel5 is an 16Bit application) that the erros message comes because the portabilized cannot be run under a 64Bit OS...
But I can run it under 32 Bit OS (WinXP, Vista Win7, Win8, Win10).
However, ther is another issue. I open a new thread because it's a different issue...