I've had this issue since the 9.15 upgrade, one positive is I download the update mod pack every day! The problem is (on the day after I've re-installed the latest upgrade with the 2 bottom options ticked (Remove the contents and Reset the game settings) ) that on the Game loading screen the orange bat gets to about 90% and the loading screen hangs for a minute and then just closes down. I can "hide" the 0.9.15 folder in the res_mods directory and I can load the game fine (but obviously with no mods). If I then un-hide the 0.9.15 folder it again fails in the same way. If I install the latest mod pack it works. Once working I can log in and out all day, but when I try the next day I'm back to square one.
Something weird going on, if you've any ideas please let me know.
P.S. Your mod pack is simply brilliant so thanks for the hard work.