when renaming an existing system the system is renamed but the former system still appears within the system explorer. After tool restart the former system is gone but the resources do not load since the SysConf.xml elements still link to the folder of the former system name
fixed in commit [1].
[1] http://git.eclipse.org/c/4diac/org.eclipse.4diac.ide.git/commit/?h=1.9.x&id=24f8247702411cbab271befeef7a792872283841