Learning Khmer Sanskrit - (Pasaa Khorm)

Below is the first Transcription

The first letter of each group of twelve is the consonant as it stands alone - e.g. "Ga" is the first letter of the page; Ga is just a consonant with no A vowel. It doesn't need an a vowel because in Sanskrit all Consonants automatically inherit the vowel A (short vowel)
The short vowel symbol for A is never used to combine with a consonant! it is only applied on it's own as a free standing vowel. So the first letter of each group of 12 is the root consonant - after that the other eleven are showing how to connect that consonant with the vowels.
The first 8 letters in the pic below are the vowel symbols if they are written without any preceding consonant. Also you should take note of the symbols underneath each consonant - these are the same letter as the above consonant, and are used if you have a double letter as in the two d's in the word "sudden".
if you take for example the letter i have indicated as "Ga", if you wrote "agga" you would have to write bothe the top and bottom letters. If you wrote just the top one twice, it woul be pronounced as "GaGa", due to the fact that all Khorm Consonants have the vowel ending of A if you just write the consonant and don't mix it with a different vowel.

Below is the English version of the transcription

I'm not sure of it's correctness it seems a little confused