Thanks again Eric, I didn't save the ESL (typical!) but had a bit more success last night I think, just working on it now but only 2 frames

The mount was already pointing at NGC2244 when I started but it was told to slew. Last night I started from a parked position which seemed to work better

In terms of settings it was 5% overlap and 2x2 with fetched info, I didn't know you could drag the centre of the mosaic but that's very handy!!