I can't seem to get this behavior working.
I have function, timeline, & textplus plugins installed.
Can't get your example to work. Nothing but a blank canvas.
Even the following yields a blank canvas:
System > On start of layout > TextPlus > Set text to "This is TextPlus"
I'm using beta release r111
I'm thinking this is a problem with the TextPlus plugin
TextPlus also does not work in the official 108.2 release.
It does work in beta r91 ( I just picked a Construct 2 release that was released the same time as the last TextPlus available on github )
Do you have the time to look into this?