Check the G-Code for the temp settings.
If there is no extreme temp written in the G-Code I suspect you print the raft quite slow?
S3D has problems if you slow down the print manually in the control panel below 50-60%.
I usually get "unresponsive" "force restart" with lines going to one endstop and back.
For complicated prints I prefer to set a relatively slow overall print speed and once it looks good I crank it up to normal in the control panel by setting the speed to 140 or 150%.
At least this way the problems at low speed won't happen.
I tried to contact the support and even uploaded some videos showing what's happening but was told my problem would be with the firmware.
Funny thing though that when using any other program for the job I can slow the printer to a dead crawl without problems.