Our reasoning is that we would enter the parametrized share name once and then select it from the drop down menu when configuring a project which is much less error prone.
I guess our request could also be to have standard destinations for a given share that would be configured in the global settings at the same time as the share. The share and the standard destinations would then be selected from drop down menus.

This is not currently how the plugin works. The share name entered on the global configuration page is THE share name, there should not be any additional path information. This is why slashes, et al, are getting escaped right now. Please open a separate request for the feature and I will debug the share name with space for this specific case.

Found that only the domain, username and password need to be URL encoded. So, I removed the URL encoding on the rest of the URL. Slashes in share names may still not work, but you filed a new issue on that request for default shares with variables.

I will close the issue after testing that Shares with spaces work on my setup. For the slashes, that is correct, I opened a separate issue for default shares with variables in the names JENKINS-8879

I'll probably do a release on Monday, the default shares will take more time and I'd like to get this bug closed out.

Agreed. The two features are independent and I will close this one when I test it with the new release.

Any update on the release which fixes the default shares with spaces so I can close out this bug?

Ah! I thought I had pushed the 1.1.14 release. I'll do that as soon as I can.

Code changed in jenkins
User: slide
Path:
src/main/java/com/slide/hudson/plugins/CIFSShare.java
http://jenkins-ci.org/commit/cifs-plugin/3e4bc02972572b9964b0cee27bf97c8c796561e7
Log:
Fixed JENKINS-8864

Tested on Windows XP with a Windows Share with a name using the cifs 1.1.14 and worked.