After generating an RSA key based CSR with a keysize of either 2048 bits, 3072 bits or 4096 bits, the new CSR still contains a public key with the larger keysize that was part of the last CSR, even if the user has selected the 1024-bits radio button. If the user presses the "Reset" button or exits and restarts CSRTool, the new CSR will be 1024-bits, but not if the next CSR is generated immediately after the last one.
The bug has been fixed in Build 29 of CSRTool (Version 0.11). The new build and sources are available at
http://sourceforge.net/projects/csrtool. No changes were made to the documentation.