The doc-string of `org-table-convert-region' doesn't specifically address 0 as SEPARATOR, but 0 is an integer. It shouldn't hang in any case. When I C-g out of the loop, my undo limit was exceeded because the line filled with hundreds of thousands of empty cells.
I think the correct behavior is to convert region into table using 0 spaces as a separator -- so each character forms its own column. -- Le Org version 7.5 Emacs 24 Jan 2011 build
