Crashes when using Hole and then collapsing remains

[Solone]

Hi
I'm building a car chassis. I was removing a bar of the chassis with Hole by first selecting an edge then its neighbours using (g hotkey) and converting that selection to faces. Hole worked fine, but then removing the 4 open edges by collapsing produces a vertex which is ok. When I seek to collapse the vertex to have a clean quad an error message pops up about hotkeys from previous versions.

Below is the crash dump. I'm on a windows 7 Core 2 Duo Acer travelmate 6492 laptop with 2GB of RAM.

Dump written 2013-2-15_3-49
Version: 1.4.1
Window: geom
Reason: function_clause

Short stack trace:
[{gb_trees,get_1,2},
{wings_we,'-do_renumber/3-lc$^0/1-0-',2},
{wings_we,do_renumber,3},
{wings_we,renumber,3},
{wings_ff_wings,renumber,5},
{wings_ff_wings,export,2},
{wings_file,save_now,2},
{wings_develop,time_command,2}]

Long stack trace:
[{gb_trees,get_1,[-1477,nil]},
{wings_we,'-do_renumber/3-lc$^0/1-0-',2},
{wings_we,do_renumber,3},
{wings_we,renumber,3},
{wings_ff_wings,renumber,5},
{wings_ff_wings,export,2},
{wings_file,save_now,2},
{wings_develop,time_command,2}]