Opening drawings from other CAD programmes

I have just started to use LibreCAD. I have been using the Draftsight CAD programme since 2011. It is probably very simple, but I cannot open drawings in .dwg format created in Draftsight in LibreCad to save and later edit them in LibreCAD - help and advice appreciated. My operating system is XP. Some of the drawings I am trying to import to LibreCAD were originally created in either AutoCAD 2006 light or AutoCAD 14 and I had no problem opening and editing them in Draftsight.  

DWG format implementation in LibreCAD is only experimental , it may work or may not, depending on dwg - version and features. If you have draftsight still working, try to save your files as dxf 2007 first before opening in LibreCAD. You may also use the Teigha - file converter, which is freeware.

Dellus. Thank you for the information, most appreciated. I tried it over the weekend, it works. Drawings from AutoCAD 2006 light + Draftsight OK. AutoCad 14 based drawings a bit "hit and  miss", Possibly as it is an older system? Also it helps to remember if drawing saved in Draftsight was in Model or Sheet when saved............