If the RD-D Help download is in the form of a ZIP file, you will need Winzip or similar software to expand it. The RD-D Help file itself will be called "rubber_help.chm". Wherever you installed Rubber Dub-Dub (e.g. c:\Program Files\Rubber), go to this folder and examine its contents. If you have run the program on at least one occasion, you should find an empty "help" sub-folder. (If not, you can create it yourself manually.) Simply copy rubber_help.chm to the "help" sub-folder. From now on, if you type the function key F1 in Rubber Dub-Dub, the Help will be shown. Alternatively, you can use the "Help/Contents..." menu on the RD-D control panel.