From the CSA2 group and Andy McFadden:
This was a relative minor release. I bumped the minor version because of the compatibility break. Changes since v4.0.5:
* Added save and restore of main window placement (issue #41).
* Added workaround for ProDOS sparse file issue (issues #15 and #49).
* Updated to modern build tools (breaks WinXP support).
This version runs on Windows 7 and later. See http://a2ciderpress.com/ for downloads for the latest version as well as older versions that run on WinXP/Vista and Win98/ME/2K.
The ProDOS sparseness issue happens (I think) because some programs expect the first block in a tree file’s master block list to be nonzero, and become sad if it isn’t. Adding zeroed-out blocks wastes a little space if the first 128KB of the file is full of zeroes, so CiderPress didn’t create them that way. Now it does. cf. https://github.com/fadden/ciderpress/issues/49