If you want to program an Ecu in MOSt network, you should be aware about the dependency among those Ecus in the same network, when an Ecu is erased, other one (at least partially) is erased too . This means, you have to flash the MOST Ecus group in a correct sequence. Or you will get the error 8352 which means Ecu is still in boot mode.
Autohex II is safe if you know what you are doing.
To solve this issue, you can use ISTA-P which will flash all Ecus in this group in the correct sequence.