I just got this message:
"Critical database error!
Something really bad happened to the database and the backup database. The only way to recover is to create a new database. This will not effect your unpulsed stats, but wipe the rest. Continue? [Yes] [No]"
I clicked [No] for now, but does this really mean I’ll lose everything? 
If you click yes, you will lose the statistics that are saved locally within the program. Data that you have pulsed to the website will remain intact.
Not everything. It’s saying you won’t lose your unpulsed keys, clicks, data usage and uptime. Just the more details stats like heatmap and per-application stats.
Ensure you pulse regularly, more reliable.