So, I just fixed the accesslevel problem and the fix it will be in the next dev. release.
here is the thing... The fix will only work properly for people updating from 3.1 as I needed to update the database. Actually it will work just fine if you started with version 3.0 and added your hotspots. If you used version 2.0 and upudated to 3.0 the access field will have the value 0 and it should be 1...
Anyway you can try the fix and if you don't see hotspots on the map this means that you have the wrong access level stored in the db (0).
You can execute the following query in the phpmyadmin:
UPDATE #__hotspots_marker SET access = 1 WHERE access = 0;
I'll publish the update later today as I want to fix few more things in it.
About php.ini - depending on your hosting you will be able to change some settings through php.ini or htaccess files. Talk with your hosting provider. In the future I actually want to have a nice media manager in hotspots.
Daniel