The Slokas in this collection are spelt correctly. I have made no concessions to fonts or systems that cannot or do not display compound letters and ligatures.
For example, the word lingam is spelt लिङ्गं. Many fonts do not have a ligature glyph for compounding ङ and ग and so display them as a sequence of characters. I could have instead, spelt the word as लिंगं, which would display correctly in most systems. Indeed, Prof. Apte's Sanskrit dictionary routinely uses this substitution for conserving space, even as he argues that it may be regarded as incorrect.
I feel that eventually, fonts will contain all the ligatures necessary, and rather than encoding these Slokas incorrectly to accomodate them until then, I will create more incentive for them to hurry.
There are several fonts mentioned in this page that you can use. The most complete font among them that I have used is called "Sanskrit 2003". It doesn't seem to be anti-aliased, but enabling font-smoothing corrects that readily.
I try not to use an anusvara in the middle of a word. Thus, simhah will be spelt सिम्हः rather than सिंहः. There is no technical or language-rule reason for this. In my experience, reading the version with the half-form is less prone to error; the anusvara in the middle of a word is easy to miss whilst speed-reading.
Either spelling is acceptable and correct.
I will use an anusvara if it appears at the end of a word. It is not as easy to miss. The exception to this is if it is the last word of a sentence or paragraph. In that case, I use the dead consonant form (म्). I believe this follows the rule of the language.