Ability score increases

[30ishMutantNinjaTurtle]

I'm sure I'm being stupid, but how do you change main stats on level up?

[Scuba72]

click the score box and type the new score. It doesn't show a cursor after you click, which is where most people get confused.

[30ishMutantNinjaTurtle]

I'll call myself 50% stupid then. That was the most obvious answer.

[GavinRuneblade]

I'll give you a bit of advice: go into the abilities tab and in the list where you see "ability score increase" unlock it and make a note of what class and level you applied what feat or stat gain. Something like:
Rogue 4: two weapon fighting
Rogue 8: +2 dex
etc.

Comes in handy.

[Griogre]

GavinRuneblade's advice is good on the abilities tab, on the original question you can also change stats by hovering the mouse over the stat and holding down Ctrl and scrolling the mouse wheel up or down to change the value.

[Three of Swords]

Another option is to type the change value into the Mod field. Then drag it to the ability score or other number value.

Very useful when adding or subtracting large 'random' values like 1387 gold pieces.

[30ishMutantNinjaTurtle]

I should ask more stupid questions. I'm learning so much.

[Three of Swords]

The first post in https://www.fantasygrounds.com/forums/showthread.php?45418-Useful-shortcuts-and-tips-to-use-in-Fantasy-Grounds is highly recommended reading. The OP compiled the suggestions in the first post so you don't need to read through it all.