Hi Valyar,
Ruleset Wizard can import only it's own projects, not Fantasy grounds rulesets and/or extensions.
About creating content for Fantasy Grounds, you must adhere to Fantasy Grounds license agreement, so you cannot create official content without SmiteWorks permission, and you cannot share copyrighted content. In addition to the software license there is some advices in the disclaimer page:
https://www.rulesetwizard.com/disclaimer/
You could use any tool you want to create commercial products (notepad++, visual studio code, Ruleset Wizard) as they are independent tools that help you creating the final product, a series of xml, lua and image files, packed together. You just have to take into account how and to whom you distribute this final product.
Ruleset Wizard supports almost any Fantasy Ground content. You can find a Combat tracker example here:
https://www.rulesetwizard.com/advanc...ombat-tracker/