GoToWebinar & some OpenSesame Courses

I have been experiencing issues trying to join a live webinar (presented through gotowebinar.com, also known as gotomeeting.com - from LogMeIn Inc.). I use a Windows Server O/S.
On both occasions I have joined the webinar successfully but the video link session window has timed out. LogMeIn support have requested remote access to my PC to troubleshoot the issue and I have declined (I have a "trust nobody policy"), so no support has been offered.
This same problem also affects my Mac laptop (running High Sierra O/S).
On Opensesame, certain (pre-recorded) video courses start, but the video player window is empty and eventually times out. (an example of this is the course named: "Azure: Advanced Virtual Machine Deployment from Intellezy (duration - 1:15hrs). Other courses work as normal. (Support from OpenSesame suggested whitelisting the following domains in my firewall
https://*.opensesame.com
https://*.jwplatform.com
https://*.jwpsrv.com
https://ssl.p.jwpcdn.com
https://jwpltx.com
If I bypass my Sense Router (and plug in directly to the Broadband hub) - the webinar works as normal, and the OpenSesame course runs perfectly.
There is no log of anything being blocked in the Sense App threats list, so I cannot create a bypass or make an exception (whitelist).
Short of always bypassing the F-Secure Sense router for GoToWebinar/GoToMeetings, and some OpenSesame courses - how do I go about resolving this issue?
By the way, Zoom Meetings and WebEx meetings both work normally through F-Secure Sense router
Thank you