running view – getting White Screen of Death

using latest versions of WP and Toolset.

View works if you have a parameter – http://www.mtctest1.com/vieq/find-healthcare-provider/?wpv_view_count=1&i=0&sp=Ambulatory+Clinic&wpv_filter_submit=Search

Any combo of choices works, BUT if you leave both blank (in effect, Select ALL) or just visit the page from the main menu, the screen goes blank. all white. Debug in WP tells me nothing (still blank screen)

Please advise.