SWTBot produces a p2 repository: http://download.eclipse.org/technology/swtbot/releases/2.3.0/
The main part of SWTBot are still meant to be compatible with older version of Eclipse (Helios and later). However, as part of this release, the default target platform for build and test execution is Eclipse Luna, and SWTBot isn't actively tested under previous versions of Eclipse.
SWTBot requires Java 6 and later, and was reproted to work as expected with Java 7 and Java 8. Other JRE versions were not tested.