Also the SiddhaṃKey site seems to have shrunk to almost nothing as well with only the front page and an image of the word Siddhaṃ left. I never used their Siddhaṃ keyboard as I don't like the CBETA font, but I did find the Lantsa keyboard useful.
I've been in touch with Khai who created both of these sites and he just says he removed them "for personal reasons". There is a possibility of having new sites so, hopefully
I've uploaded the CBETA Siddham font to my site. You can download it from there. It has some limitations and I don't personally use it, but it would be a shame if it disappeared completely. I note it has been used extensively on the Wikipedia Siddhaṃ page.