I have tested. Single player works for me. I have followed demulshooter instructions to configure the plugin input type option to multiplayer and created a AHK script, but had no luck running dual GUN4IR's
AHK script:
Run, The House of the Dead Remake.exe
Run, E:\DemulShooter\DemulShooter.exe -target=windows -rom=hotdra
Escape::
Process,Close,The House of the Dead Remake.exe
Run,taskkill /im "The House of the Dead Remake.exe" /F
Process,Close,DemulShooter.exe
Run,taskkill /im "DemulShooter.exe" /F
ExitApp
return
replacing DemulShooter.exe in the script with DemulShooterX64.exe does not close down demulshooter properly. When exiting the game it still runs in the background along with the AHK script. Thats why i am currently using DemulShooter.exe