Doh, my bad. I added a feature that let’s you compile/run code without first saving it. To do this I create a temporary file of the text you’re trying to compile and then compile that file. I didn’t change one variable in the PropBasic module which caused ViewPort to look for the error log and resulting spin file in the wrong place. My regression test passed because the spin file already existed- I’ve fixed both issues and will upload a new version in a couple hours.
Regarding "edit3". Try pressing "Load" instead of "Run", this should do exactly what BST does, just compile without VP support to spin and then load to the Prop. Adding VP support does require some memory and a cog, this may push you over. If you’re willing, send me your code.