I am attempting to pass parameters from one SharePoint list to another using the URL. The aim is to ultimately redirect to a nondefault page after user completes action, but all Im interested in now is getting the URL right. Here is how I am building the URL query string in the source document:
<xsl:variable name="URL" select="concat(
'../Waiting List/register.aspx?
" />

and this is the URL it results in:

http://<servername>/training/admin/Lists/Waiting%20List/register.aspx?CourseID=1&CourseTitle=Introduction to Excel 2010&Source=confirmation%2Easpx%3FID%3D1&Source=http%3A%2F%2F<servername>%2Ftraining%2Fadmin%2FLists %2FCourses1%2FDispForm%2Easpx

Source appears twice which is obviously not right.

Can anyone see what it wrong with my XSL?

Thank you