Thanks Simon, that's a nice setup - love the weatherproof box!
Hmm, my fear is that yes its the driver but I don't know how to update it (I presume that's an EKOS thing - not sure how I can update just one device driver within EKOS?). I'm running 3.5.4 on a laptop - it doesn't look another device is trying to block it, it just doesn't see it (no USB blocked access messages arrive). It clearly looks for the Atik b/c an error message comes up saying check the device is on (it is) & connected (it is). But in the INDI Manager menu, there isn't even a tab for the EFW2 (normally even if a device is struggling to connect, it would have a tab there - but since that tab doesn't even appear, I'm thinking there may be a glitch somewhere where it knows it needs to find an Atik EFW2 but then...).