Can't say by the moment if this is a regression, more tests are upcoming, what can I describe is the symptoms of the bug.
Enviroment: nightly build 20210411-0.4.15-dev-2343-ge044df8
VM: Qemu 0.9.1, Fat32 partition.
1) Run any .exe file (i.e from the cmd)
2) after successful running, close the app (make sure it's not open with taskmgr)
3) try to delete it (i.e with delete command)
The file is held by the system, throws the error "Access is denied"
In Win XP you could delete the file without problems.
Surprisingly, the file can be renamed (and maybe even moved to other folder) and replaced by another file with the same old name, but still cannot be deleted.
To free the file you must reboot the system, but as long as you run again the file, it keeps held until next reboot.
Debug log attached.