To people who come here with various "issues" and "bugs" - it's your game, not this trainer. All what this trainer does is in it's options. Those options either work or they do not. Whatever strange behavior or issues you may get in the game are coming from your game or your attempts at changing something within it using other tools or means and are not related to this trainer in any way, so please don't write about them here.
Of course, the trainer itself does have one issue what I can tell of and that's the "infinite weight" bug, specifically it seems that the option is bugged and does not actually grant the 1000 inventory size. It either may remain at 60 max or may go to -30/60, and if you use it it may also add some "ghost items" to your inventory. But that also is the ONLY bug what it has, so simply don't use that option. Use other tools or trainers out there if you want to get that feature.
For other features, check the video at the start of the game and the short instructions. Some options will become only available when specific conditions are met, for example you cannot add any inquisition perk points until you actually earn your first inquisition perk point. This is needed because the trainer needs to actually see that point and "lock on" to it, if you have no points the trainer has nothing to aim for. Some features will be enabled once the trainer, again, can "see them", so check the instructions and video again. And yes, the mega XP option also works but it has some requirements: first, you can only get "mega XP" if you are actually getting XP in the game, so if you're already 4 levels above the level of opponents, you will NOT get any XP anymore by killing them. It's the game feature, not the trainer issue. You will still get the XP whenever you read any book or letter what you don't have yet in your C o d e x. Note also that whenever you LOAD a new area, LOAD a new game or CHANGE your party the Mega XP option gets disabled, to re-enable it you will have to turn off all the options (press the appropriate F-keys), turn off the trainer (press F1) and then turn the trainer on again (F1 key again). Then re-enable all the options you had on (F-keys again) including the "Mega XP" option and done, it works. This is not a bug, this is how the game behaves, addresses and values change locations and trainer needs to find them again, thus these steps are needed. And of course you use those F-keys while you're IN GAME and the trainer is running on the background.
So, as a conclusion of this post - trainer works 99%, it does what it says it should do and any weird stuff you may get are really just your stuff and not related to the trainer. Personally I also hope that MrAntiFun will have one day the time to also look into this inventory issue, but other then that, it all works. Read the instructions people, and watch the video.
