I created Slax modules for FreeBASIC, FreeBASIC Manual and FBHelp. For FreeBASIC, some SVN builds are also available because some bugs present in version 0.21.1 are already fixed in the SVN. FreeBASIC is available in prefix and standalone versions, FreeBASIC Manual is available in HTML format, and FBHelp is available in CLI and GUI builds. Standalone versions of FreeBASIC have GNU toolset and libraries from FreeBASIC 0.20.0, since the files from FreeBASIC 0.21.1 needs glibc 2.8.
FBHelp already have a copy of the manual in DAZ format; if you prefer FBHelp than your web browser as your help viewer, you don't need the FreeBASIC Manual, and vice-versa.
If you need an IDE for FreeBASIC, Geany 0.19.1 is also available here.
Slax build scripts for the modules are also available for download (note that the modules also have them). Log files from building the modules are also available.
If you don't know how to use them, just download the module you want by right-clicking the link, click "Save Link As" (or similar) in the menu that will be shown, and double-click the downloaded file in the file manager; then Slax will activate them automatically. Read this for more information.
You could only use one module per type (one compiler, one manual and one help viewer). Not following this will overwrite the files of other modules.
Slax Devel module is required by the FreeBASIC Compiler and is installed by default in Slax. If you have a customized Slax, the author (or you) might have removed it to conserve space. To check if it is installed, type gcc in the terminal then press enter; if it showed "-bash: l: command not found", it means you don't have the devel module installed. In that case, download it from here.
Tested for use in Slax 6.1.2, though they are not well tested, since I use Ubuntu as my operating system.