I run into the same crash here after doing the same things (same exception in the same function). I'm unable to actually interact with the error/report tool or I'd send the crash report. Big box prevents anything from coming to the foreground, even after the crash. I was able to open task manager and leave it running for a minute, close big box and see that it appears it's running out of memory, consuming over 90% of 16GB of RAM. I imagine the crash is related to trying to get another chunk and being told it can't get it, but that's just a hunch, haha.
This occurred for me last night running 10.11, and tonight running 10.12.
Also, it's interesting to me that I see classes related to VLC player showing up in that call stack. My config had been set up to use Windows Media for video. I saw that the UI indicated VLC was recommended, but I think mine defaulted to using Windows Media. I'm not 100% because I initially installed and set this up on my desktop and then copied the whole install to my arcade machine after I built that system. My intent was actually to eventually set up an rsync job or robocopy job to keep the media in sync between both systems. (I left this set up to use Windows Media even though VLC was recommended after noticing that the Big Box UI seemed sluggish and I spotted in a Youtube video someone complaining about performance in Big Box and noticing that the issue seemed to be resolved for him when disabling VLC player. I see similar performance impacts from disabling VLC as that guy.)
Edit: 10.13 just installed. I'm also trying some tips from the performance thread. The main one is installing the K-Lite codec pack. I use that on other PCs to great success and since this was a fresh OS install I hadn't installed anything in that area yet. Oh, for reference
Windows 10
Ryzen 5 3600
16GB PC3200 RAM
1TB Sabrent Rocket M.2 for Launchbox install/media
240GB SATA SSD for OS install
ROMs are accessed via junction to SMB share on 10TB RAID 0 with 800GB SATA SSD Cache on my desktop.
~11K games