I have encountered the exact same bug mentioned here. I do feel it is slightly different from the enhancer bug they mentioned in the Release Notes, but hopefully the both get fixed as I have over 1k tied up at the moment. My exact issue is as follows...
If I try to sell @ Trade Terminal;
"Only empty containers may be traded or be placed"
If I try to put on auction;
"This item cannot be traded."
I don't use enhancers but seems to happen to any finder, armor or weapon (L or UL) that has had an attachment (amplifier) put on it. The attachments themselves do not get locked.
This also is happening with 2 Quad-wings that had thrusters attached. The Quads will also sometime get an error when exiting a planet atmosphere. The error is about items in vehicle inventory. EU sees 1 item in vehicle inventory when in reality there is nothing inside.
I submitted a support case a while back which was immediately closed with the following copy/paste response;
"Thank you for your report.
We have forwarded the issue to members of the responsible team for further investigation, any irregularities found will be adjusted as soon as possible.
Please stay tuned to the News and Release Notes sections on the website for further information and developments.
Thank you for your patience."
Which I feel is vague and impersonal. Just thought I'd share for whatever it's worth, quite annoying as I have been test driving various armor/plate and finder/amp combinations.