'Excluded files and locations' did not fix it here, i had to add all of PureBasic's .EXE to the
'Excluded Processes':
Run with PB 32bit and 64bit and [Copy] the debug output to MSE Settings -> 'Excluded Processes' (CTRL+V to Paste it) and press [Add] there in MSE.
Code:
pbDir$ = #PB_Compiler_Home
Debug pbDir$+"PureBasic.exe;"
Debug pbDir$+"Visual Designer.exe;"
Debug pbDir$+"Compilers\"+"pbcompiler.exe;"
Debug pbDir$+"Compilers\"+"PBDebugger.exe;"
Debug pbDir$+"Compilers\"+"PBDebuggerUnicode.exe;"
Debug pbDir$+"Compilers\"+"FAsm.exe;"
Debug pbDir$+"Compilers\"+"porc.exe;"
Debug pbDir$+"Compilers\"+"polib.exe;"
Debug pbDir$+"Compilers\"+"polink.exe;"
Compilation time is very fast again.

Executable startup still takes half a second. To speed it up, exclude the following files too, if you want:
Code:
tmp$ = GetEnvironmentVariable("TEMP")
For i = 0 To 9
Debug tmp$+"\PureBasic_Compilation"+Str(i)+".exe;"
Next
Seems to be important to MSE that Paths and File names are case sensitive, so
it has to be "Compilers\", not "compilers\".
I had already manually entered almost all of these, with no luck, so I tried pasting in the output. Unfortunately, it did not help either. I am running w7-32 with msse. I guess it is time to find a new av. Between my laptop being a couple years old, and my code being long, the av now adds over 20 seconds to the startup time, and that severely slows down debugging. (I can create a LOT of bugs in 20 seconds!