It seems that zukow, possibly together with other betatesters/Development Team members, have isolated issue(s) that are causing the issue(s) with SCANdal to fail to communicate or interrupt/stall the USB process with Poseidon. I am not sure which one or both of these issues will be addressed, but in MorphOS: Public Release of MorphOS 3.15 .... at 0921hrs 3-Jan-2021 in that thread zukow states the workaround will be provided in 2 weeks.