FSX & TrafficX/Traffic360

Firstly I need to make a couple of points.
I have no connections with JF other than occasionally purchasing products from time to time - and I would also add that I consider some of their products to be less than fully tested when they are issued to the public.
I have been running Traffic X for many years now. It took me some time to get to grips with the user interfaces but have got to the point where I am content to stay with it rather than migrate to Traffic 360. Traffic X does what it set out to do without any special fiddling about but some tinkering was necessary to correct some elements of aircraft behaviour. When T360 first came out, I purchased the upgrade version but held off as too many users were reporting problems. I now have the latest T360 installed as a dummy program on my laptop so that I can look at it without affecting my FSXA / Traffic X installation.
Now to try and respond to some of your problems.
You seem to have installed and un-installed TX and T360 several times. When un-installing do you go in to the file system and clear out any remaining files that get left behind? It is essential to do this.
If TX is installed, in the FSX Scenery Library you should get an entry "Traffic X Airport Facilities". It will initially appear at the top of the list but you must move it down below any of your other scenery addons so that they appear, rather than the TX airport versions. If you haven't got this entry, the installation is not correct and I cannot understand how TX can be said to be working?
When TX is installed, a file "TrafficX.bgl" (dated 18/11/2008 85,898Kb) is placed in '\FSX\scenery\world\scenery\'. This is the default BGL file created from the initial flight schedules supplied in TX.
The Ryanair schedules are located in a file '\FSX\JustFlight\TrafficX\presets\data\schedules\flight plans\RYR.tcc'. As installed, this contains over 90 different flight schedules for Ryanair. Of these, over 50 go to and from Stansted (EGSS). Bearing in mind that the TX compiler adds a percentage figure to all flights that controls whether a given flight will be seen in FSX dependent upon the 'airline' setting in FSX, a good number of these 50 should show up at EGSS if your setting is say 70% (which is my normal setting).

In T360, JF have done (in my opinion) some strange tinkering with how schedules are handled.
You should get an entry like "Traffic 360 airport facilities" which should be handled similarly to above.
The supplied default AI file is called "ai-traffic.bgl" (17/03/2013 102,328Kb).
JF have offered 6 different ranges of flight schedules for different 'years' and different 'seasons' (gone a bit too far in my opinion). I guess that the default AI file will contain a load of Ryanair flights but I haven't been able to check this out yet.
Of the 6 'year/season' schedules, only 3 contain flights for Ryanair - Summer 2007 (94 schedules), Summer 2011 (94 schedules) and Winter 2013 (774 schedules). (Don't understand this last one at the moment). All 3 of these have a good number of Ryanair flights passing thru EGSS so there should not be any problems seeing them.

So, you say you do not see Ryanair at EGSS (FSX default). What TrafficX aircraft do you see at EGSS? Loads of different airlines like I do or hardly any? What is your 'Airlines' setting in FSX? Have you been doing any compiling from TX or T360 using 'Traffic Movements'? In TX, it is possible to generate a Ryanair-AI-only BGL from Traffic Movements. Have you tried that? Do you have any Ryanair aircraft at other airports - there must be some at Luton EGGW?

Can I suggest you do a CLEAN install of Traffic X and perhaps we can take it from there?

Have you read the forum thread that mentions old-style BGL files stopping other later BGL's from functioning? Have you ever had any older AI programs running?

I have just decompiled the supplied T360 AI file "ai-aircraft.bgl" and found that it contains over 700 scheduled flights for Ryanair using the 2 B737-800's that are included in the aircraft. Plenty of these 700+ go to and from Stansted and to and from Dublin. There is a good spread of "%" values which means that if your 'airlines' setting in FSX is at least 50%, then there is no reason why Ryanair should not be present at Stansted and Dublin airports (at least from the Traffic 360 point of view). If they are not there, there must be a non-Traffic 360 problem.
I would point out that I am talking about the default AI file here, if you have tried to create your own compiled files then I cannot comment on the results that you are getting.

Thanks guys. Very helpful information. I have tried some of RayM's options and finally got a few Ryanair at Dublin/Stansted. Will do some more juggling and see what happens and get back with my further comments.