Show merge network error

Have a new show that only contains 2 custom LED fixtures created by HES.

Have an existing show (very small) that I need to merge the 2 LED fixtures into. Every time I try to do this I keep getting a Network Error has occurred, either wait for task to complete or cancel it.

I keep hitting Wait button (takes about 2 minutes to appear each time), but the show will not merge.

Running Windows 7, 32 bit. Latest release (3.1.6).

Thanks,
Ross
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