I don't know the first thing about EME engines and nothing about twins but I'll try and help. It could be that your prop isn't clocked correctly. Zenoah engines have to be flipped different from others (not on the compression stroke). Your EME could be like that. Double check what is in the manual. You could also try using an electric starter.

When I prime a gas engine I hold my finger over the end of the carb and pull it through with the prop until my finger is wet. That usually doesn't take but a minute. If your finger is just not getting wet then you have a fuel draw issue. You could be sucking air at the carb intake or the diaphram is bad (I know this is a new engine but it could still be bad).

It also could be that the engine is so new that it will need to be run to get broken in. After it's had some time on it, it may get much easier to start and run. I wouldn't give up on it.

carl