I want to use the text-watermark plugin, but i cannot find documentation on how to install or use it...
http://www.zenphoto.org/2009/10/new-plugin-text-watermark
Yes, there is a folder and a file, that is standard structure of plugins that have additional files. Place both in the plugins folder. It is a n older plugin and may not work in the /plugins folder (I think it is from before that change). Try the zp-core/zp-extensions instead.
Generally it is not a official supported plugin (although sbillard made it) and provided "as is" (indicated by the red icon). I also have never tried it myself.
The plugin was designed for the current external plugin structure. Install as acrylian decribes initially. Emable it and create your watermarks.
The text watermark plugin simply creates a watermark for you. It will have a name based on the text you entered. You must also assign that watermark to whatever you wish to have it applied.
aha!
[Tue Jan 12 18:56:09 2010] [error] [client 195.241.126.190] client denied by server configuration: /home/deb26637/domains/-mysite-.nl/public_html/demo-01/plugins/text_watermark/createwatermark.php, referer: http://www.-mysite-.nl/demo-01/zp-core/admin-options.php?saved&tab=plugin