Run 2 "MakeVB6" steps at one time?

[FeedMe]

I have a parent and child project that both run "make VB6"

If one of the VB projects does not compile I get an error opening the file vsmake.err and the actual compile error is lost.

Both "Make VB6" commands use the switch /out %temp%/VsMake.err and I cannot see any way to change it.

Is there a way to change the /out switch so I can have a unique file for each instance of "Make VB6"?