You're not the first one (nor the last one) to have problems with downloads in that app.
I too see downloads dropped or just not updated after a lengthy download.
The sure fire way to update your data (charts, procs etc) is to delete all, restart app and download needed data from scratch. So whenever in doubt, try that.
(though the Android app WILL try to fight you on that; they still haven't figured out how Android works )