The plugin Mark%2666, for example, VAM will modify the URL to ...Mark\%2666... As a result, CURL don't know how to download it, and so fails to install.
BTW, I'm using Windows.
First % is only the storage location, not the download url.
If windows doesn't like % (because it has special meaning?) we have to fix the quoting.
As a quick fix you can get all plugins by http://vam.mawercer.de/.
Something like this tells VAM to replace % by _:
let dir = vam#DefaultPluginDirFromName
return substitute(dir,'%','_', 'g')
let g:vim_addon_manager['plugin_dir_by_name'] = 'MyPluginDirFromName'
If you want to help us find the correct way to quote '%' signs have a look at the function
fun! vam#utils#Download(url, targetFile)
which is using RunInShell which calls ShellDSL
I may be able to provide a fix within 4 days or so if I can reproduce the issue.
I've fixed it by adding the hack above to the downloader when choosing target Windows. Please note that there was a small bug. Of course the line should have been:
let dir = vam#DefaultPluginDirFromName(a:name)