Thanks - I tried a few things, and it seems to have finally gone through (Perhaps this will help one or more other people):
* Went through inputs - checked that 0 or 0.00 values were present where blank and 0 made sense
* Deleted and re-did state return after seeing somewhere else that it may help (still failed, but perhaps multiple issues present?)
* The help within the web interface had a link to the 1095-SA form I think it was, which I think going through that (I think again to say that there wasn't one expected/present) seemed to lead to it working. It seemed to finally go through after this form go-through/re-go-through.
