Khmer Unicode Font Error: unable to type two vowels for one consonant

I can't type two vowels for one consonant in a newly created document of both MS Word and OpenOffice for Mac OS Sierra. I couldn't type the word below pronounced as /pei/.

I tried both ways below but it didn't work.

Surprisingly, it worked for the word 'eat' in Khmer.

This problem didn't happen when I typed the word in Chrome's address bar. I tried to type the word using the fonts Khmer OS System, Khmer OS Content, Khmer OS Battambang, Koh Santepheap, and DaunPenh in MS Word and OpenOffice but still no luck. At last, I found one that worked for me. It was Kh Battambang. I think it came with Mac OS by default because it showed in the Computer list in Font Book application.

Microsoft Word document saved in Windows 7 does not display correctly on Mac OS

I created a Microsoft Word document on Windows 7. The fonts I used in the document were Khmer OS Battambang and Khmer Mool. After that I opened it in Microsoft Word on Mac OS Sierra and the text did not display correctly. Please see the image below for how it looked like.

The problem I'm trying to fix in this post is some vowels and consonants overlapped each other. Those texts were displayed using Khmer OS Battambang font. (The square symbols resulted from missing the font Khmer Mool.)

When I copied the text and pasted it to the browser's address bar, they displayed correctly. I then created a new document in MS Word and paste it to the new document, and it still didn't work. It seemed that the problem is with the MS Word for Mac.

There are 2 workarounds:

1. Installed OpenOffice then opened the document in it, and the text was fine but the symbols in the third line were replaced by square symbols. 
2. You have to replace Khmer OS Battambang with Kh Battambang and make sure you install the font in another computer too. This is because the Khmer Unicode keyboard layout I installed was created to use with Kh Battambang font. If you need another font similar to Limon R1, you can use Kh Muol.

Installing Khmer Unicode Font on Windows 7

1. Download the installation file from here and install it
2. Manually install the fonts
   - Download fonts LimonS1 and LimonR1
   - Double click on them and click on Install button