My demo is running without TS started, and I'm still getting "No data!" errors. So, TS is definitely not the culprit. At least, 1.13 now survives those errors and keeps trading.

From my experience, TS in no way interacts with Zorro. Yes, they're typically logged into the same FXCM account, but I've never had a problem because of that.

The limitation of only one connection to the broker from one machine exists only in Zorro's FXCM.dll. And only in the free Zorro version, says jcl.