Well... the only indirect command processor present on RSXM70.DSK was ICX.TSK I transferred it from simh RX50 disk image to a RT-11 formatted floppy with PUTR (copy /binary) and then with FLX
FLX> DU0:=DU1:ICX.TSK /RT Then > REM ...AT. > INS $ICX.TSK >@[1,2]STARTUP.CMD and got a BIG system crash So they are definitely not compatible. I've got a 4.2 RSX-11M plus tape set. I'll try to install it on simh and see if they are binary compatibles...