Are there any guidelines for implementing versioned downloads of tools?
CVS is useful tool for implementing both versioning and download facilities. However, developers must implement Software Configuration Management (SCM), which goes beyondsimple versioning (see, e.g., http://www.sei.cmu.edu/legacy/scm/). There are many public domain tools (http://www.cmcrossroads.com/bradapp/links/scm-links.html#Free_CM_Tools), as well as commercial tools (http://www.cmcrossroads.com/bradapp/links/scm-links.html#Com_CM_Vends) available for SCM.