Troubleshooting XSLT compile error. Could not find a part of the path 'C:\_layouts\xsl\main.xsl'

Troubleshooting XSLT compile error. Could not find a part of the path
'C:\_layouts\xsl\main.xsl'

I am creating my own site template for SharePoint. Everything has been
going fine, building fine, deploying fine. For unrelated reasons, I needed
to reboot my development server. I then made an update to my custom.xsl
file and attempted to deploy in Visual Studio 2012. Even though it says
Deployed Successfully, My changes are not reflected in SharePoint, and I
received the error in my question. Additionally, I am getting 32 warnings
that this or that attribute is not declared, even though I made one small
change (added a link for testing) to the blog.xsl I copied my custom .xsl
from. I reverted all changes, attempted to deploy again, but cannot get
past this error now.
Any ideas where to start looking to solve this? Needless to say _layouts
is NOT in the root of the C drive, but it the 14 hive under Templates.