A security risk has been identified with ALL versions of SLP prior to 3.8.7.
It is recommended you either upgrade to 3.8.7 immediately (it is going out now) OR delete the downloadcsv.php file from the main directory for the SLP plugin.
Downloadcsv.php is only needed if you are downloading CSV files from the Pro Pack reports tab. If you use that feature you should absolutely upgrade to 3.8.7. For everyone else either upgrade or delete that downloadcsv.php file ASAP.
As for 3.8.7, I was in the middle of doing a couple very minor updates, so there is actually and improved icon processor for map markers. I wasn't intending on releasing it this quickly but it got a "free ride" with the security patch.
BTW, if you are not seeing the update to the base plugin try going to the dashboard and finding the "check for upgrade" button for WordPress itself. That button triggers a check for updates on all the plugins as well. It doesn't RUN the updates, just checks if any are available. Otherwise you will be waiting up to 12-hours for the update notification from WordPress.