I currently have a survey set up using LimeSurvey 2.64.3 (I think is an older version now?) which is what my institution uses.
It is not only an "older version", I would consider it "ancient". And the branch you are using was one of the worst releases of Limesurvey, full of bugs, almost daily new releases due to so many bugs. Actually, in my opinion, this version should have never been used in a productive enviroment in the first place. Using this still today (over 5 years later) doesn't make it better. This little monster was released on 27/03/2017:
forums.limesurvey.org/forum/news/109838-...uild-170327-released
And this isn't even the latest version of this release, which ended somewhere at 2.7x.
So maybe you should let your institution know that they really, really, really need to make an update, ideally to the latest version of LS5. But I know how this goes. Universities are really, really bad at updating.
You need to add &NEWTEST=Y to the end of the URL:
forums.limesurvey.org/forum/design-issue...e-url-with-newtest-y