request for explanatory/debug mode/display
 

So the Paizo systems are complex, and there are chains of logic resutling in single numbers. Take, for example, the number of languages known...

In Starfinder:
Common, Race, Home-planet, Int.
Culture adds +1 per rank.
Unless you have one of a set of Themes or Class abilities which affect the number of starting languages, languages by level, or languages per Culture Rank.
Simple enough for a cunningly coded program. ... but.... for a bear of limited brain, I'd love something which displayed how/why HLO had reached the conclusion it had.
Most especially, if I make a later change, and something becomes invalid, I'd like to explore why.
I can restore the removed feature. Fine. Not broken. But why dos removing it break something else. I;d like to interpret what chain leads to current selections; ake a change; see why it no longer qualifies. Maybe pick an alternate option which requalifies.

(ex-PCGen GM. So I'm used to using their "troubleshooting" sheet. Not perfect. Actually, far from perfect. But so much better than nothing!)

HLC had a tooltip that popped up on each field showing the breakdown of how each of the displayed numbers were calculated. Does such a thing exist on HLO?

It's a mix. If you click on something with a calculated number on the Play pages or the main page for that thing it might tell you all the numbers involved (Skills, for example) or it might not (Weapons). Things like "Why should I have 6 Languages?" aren't displayed anywhere.

On the flip side: if you make a change and now there's an error, go read whatever it is you changed. The tool isn't a replacement for the rules. Still, I agree that it would be good for HLO to help you if it can; see the other post about errors bringing you to where you might fix them.