Like others I have been experiencing the low frame rates on the ECML route, as low as 4 fps, where as before the update last week i was getting 35+ at the same places, particularly leaving Kings Cross.
So for the hell of it I opened the route (not session) for edit in surveyor (which we can now do in TR2019) and then straight away did a 'save as'. When I then reloaded my new copy of the route the performance was back and i am again getting 35 fps at Kings Cross. So i suspect that that the package files or the un-packaging process is causing some file corruption somewhere? Strange how it doesn't seem to effect everyone, but these problems can be like that.
Obviously using 'saving as' the route ends up with my userID (KUID) so the sessions are not linked. However, if you open the route from the Content Manager, update the KUID in the config file to the original KUID, incremented by 1, and then re-import, it makes the current version obsolete and list the new modified route as 'Modified Payware' and then all the sessions can be used as normal.
Perhaps not ideal, but a work around that makes the route usable, whilst Tony and his team sort out the bigger issues.