Hi Fellippe,
I've just ran my multi lingual install script on a baremetal system (my iMac 27 with an i7 and 32 Gb of RAM) with both Debian 8 and Debian 9 in live sessions and here are the results.
1) The BAD news is that the current InForm Beta 8 has the same problem on a baremetal system than on a VM, and to be honest I didn't expected anything else since I mainly use VMware Fusion for all my VMs and not VirtualBox (that has so many problems).
2) But the GOOD news is that the two fixes you sent me (UiEditor.bas and UiEditorPreview.bas) work like a charm on my baremetal system exactly as they do on Vms.
So, you found and fixed the problem for Debian 8 & 9 and you can add your modifications right now without holding them for your next beta.
BTW, do you want I try with other older Debian releases (i.e. 6 or 7 that are not supported anymore) ?
Hope this helps.
Cheers.
Fifi