An updated version of this keyboard with some missing characters is now available. See this post for details of the improved layout and links to the new files.
Sometimes it is useful to write Sanskrit and other Indic languages in a form that is unambiguous but can be easily read by people who know the Latin alphabet. The standard ways of doing this are with IAST or ISO 15919. The two schemes are almost identical. An example is ताण्डव which can b written as Tāṇḍava. I have produced a windows keyboard that contains the necessary diacritics (accent marks). The normal keys are assigned the same as the standard UK keyboard, only the characters accessed with the AltGr and Shift-AltGr change.