Hi, sorry to hear about the issues.
First, please let us know what OS, Reaper version, H949 version, and plugin format you are using. Please also confirm you are using the latest H949 (3.9.8) from our website, and the latest iLok License Manager from http://www.ilok.com.
For presets – are you looking in the H949's preset bar, or in REAPER's menu bar? The presets are in the custom H949 Preset bar. You could also check C:Users<username>DocumentsEventideH949 Harmonizer (Windows) or ~/Music/Eventide/H949 Harmonizer (macOS) to see if the preset files exist there.
As far as the plugin being unresponsive – can you interact with the UI at all, or is everything frozen? (I.e. is at an audio issue or UI and audio issue?)
It sounds like you had a previous version that was working – any idea what that version might have been?