Quick fix for leaky shower?

[SpadesOfGlory]

Before someone says it's a job for a plumber...I know, I just can't get one to actually turn up and look at it when he says he's going to!

I have a hi-flow shower drain in both my en suite and main bathroom showers. They have recently both started leaking very slightly and closer examination shows that the plastic ring that the chrome waste sits on is lifting ever so slightly so there is a tiny gap between it and the shower tray. (Sorry, don't know the technical terms!!)

I imagine the waste pipe needs siliconed from underneath, but the floor is tiled and grouted right up to the removable panel so I don't want to attempt this myself.

Would it be really awful to tape it down from the shower tray side with clear waterproof gorilla tape as a temporary measure until after christmas?

We'll, if you can't get it sorted professionally before Christmas, doing something to stop the water from seeping under the fitting and soaking through the subfloor (and ceiling below?) is better than doing nothing IMHO.

Is there a screw in the middle of the plughole?

@PigletJohn Yes there is a screw, but it's in the bit that lifts out to access the hair trap etc.

It's a shower in a new build so I'm pretty sure the builder will have used the cheapest possible options when fitting. Been in the house 2.5 years and had no other major issues though so not the usual horror story of buying a new build.

If you can see a makers name, you might be able to look up the installation instructions to see if it can be tightened from above. But I fear it can only be done from below.

You might recognise it if you scan Plumbase, Screwfix, and Travis Perkins websites. It's called a Shower Waste, not a Drain.