rnd-20060511-1-src

rnd-20060511-1-src
* changed level file format by adding two new chunks "CUSX" (for custom
  elements, replacing the previous "CUS4" chunk) and "GRPX" (for group
  elements, replacing the previous "GRP1" chunk); these new IFF style
  chunks use the new and flexible "micro chunks inside chunks" technique
  already used with the new "CONF" chunk (for normal element properties)
  which makes it possible to easily extend the existing level format
  (instead of using fixed-length chunks like before, which are either
  too big due to reserved bytes for future use, or too small when those
  reserved bytes have all been used and even more data should be stored,
  requiring the replacement by new and larger chunks just like it went
  with "CUS1" to "CUS4"); this whole problem now does not exist anymore