When I start putting together the code that loads it all up in the app, I realised that I'd botched it. So, going back to the start, and making an adjustment in all the code I'd written so that it had an extra (needed) field that I'd not thought of, and I was finally up and running.
I've also been adding in code that handles proper skill requirements, so you need to develop some skills in particular order, or at least open them up. For example, in the example shown from the Rogue Shadows Tree, the opening skill here is Backstab, but once that is active, you can spend points into Unseen Hand or Melt Away and so on.
You can also see that skills show an A, P or U - which shows what type of skill they are. Active skills are skills that need to be used, whether in combat or outside to provide a benefit. Passive skills are simply always on and will generally give a continuous buff of sorts, Lastly, Unlock skills merely unlock an ability type, and you will need to learn abilities that use this slot. A good example is these are in the Mage trees. Unlocking a type of spell class, for example "Elemental Fire" spells won't grant you the ability to cast anything on it's own, but if you find, buy or quest for spells in that category, you'll be able to cast them - so a single skill can unlock MANY different abilities.
The code for these is taking some time to write, and I've been quite busy of late,m so my normal programming hours are being cut into as it is, so I'll probably be able to do some updates here speaking to the various classes and skill trees more!