The formula solver is a great feature that I've used on numerous occasions.
I noted recently on a cache with 15 variables that the Solve, Cancel and Save options were not displayed at the bottom of the variables. You thus cannot use this formula solver with this many variables. I haven't experienced this before but I don't think I've done any other multis with more than 10 variables.
These buttons should be displayed so you can use the solver on these caches.
Cache, which had this issue was GC9DMX2
NAB CD.EFG WHIJ KL.MNO
I've attached images to show the missing buttons at the bottom of the 15 variable list.
Sorry for the delay... didn't notice the post.
I have a fix for this in an upcoming release. Thanks for letting me know!