Took some time to properly configure my network for WebGizmo (was defaulting to a NAS connected direct) and now videos just show spinning wheel like they are loading and won't play.
Everything seems to be set up properly, thumbs build fast on this 50 video playlist I made, and those videos play back fin on server.
Media Center
Install Path: C:\Program Files (x86)\J River\Media Center 17\
Interface Plugins: TiVo Server (not running)
JRMark: 4379 (version 17.0.133)
Library: 402458 files, 63.2 MB in library, 2.8 GB in thumbnails
Resources: 121 MB memory, 555 handles
Version: 17.0.147.0 Registered
Computer
ACPI x64-based PC (driver 6.1.7600.16385)
Disk drives
Corsair Force GT ATA Device (driver 6.1.7600.16385)
Display adapters
AMD Radeon HD 6570 (driver 8.961.0.0)