I had that model light a few years back and the housing pulling back is normal.. You have to double click the switch for initial firing..

There have been some people that were able to rewire the battery to use an oem battery setup on candlepowerforums.net

If you need a new battery, it will set you back 150-200.00 direct from L&M.. The original charger was a nimh charger, the newer model chargers are what is called a multi-chem charger which will charge all batteries from L&M.. Choose battery carefully so it matches your charger.. Sometimes you can find batteries on ebay..