Problems - a subforum here in another language becomes inaccessible to most Brits and Americans - we are famously bad at other languages. We are however the majority users here so that counts as a strong voice.
Then a subforum in Arabic, or Chinese or Spanish not only cuts out most English speakers, it cuts out all the other language speakers too.
Solution? If it was possible to do, an addon which applied a translator PER POST might be good.
Then the source material would stay in English, making it available to the great majority, and translatable as a common source to those that need translation. Someone struggling with the meaning could switch temporarily to get help.
But I don't know if that would be doable..
With or without a software solution, there are some basic guidelines that help when providing support to someone who clearly has limited English. I'll try to remember them because I'm so used to it I don't think about it. I mostly write like that anyway because of long years as a teacher.
Actually language made suitable for a non-native-English speaker is also excellent for sharp, focused clarity for any support work with English speakers too. We all feel a bit nervous when tackling what we do not know, so short, simple, childlike language is much easier and psychologically reassuring.
1. Do not use slang.
Use 'educated English' as much as possible as that is what foreigners usually learn.
2. Do not use short forms like 'max' 'min' 'mins.'
Learners tend to learn full forms first, short forms later.
It even helps not to use can't, doesn't - use cannot, does not.
3. Do not use acronyms (sets of letters as short forms) unless they are names of software without a long form in use eg. MSWord.
4. When using a word outside a child's vocabulary, like 'acronym' put its meaning in brackets as I did above.
5. Make lines or sentences as short as possible.
Aim for a child's book style. This keeps lumps of information small to digest. AVOID 'AND.'
6. Write in list form like this, not in paragraphs.
Single lines or two lines maximum are easier to digest, less intimidating.
7. Try to use one word verbs/ action words eg. use descend instead of 'go down;'
One word action words come from Latin a big root language for Europe. Most European languages have similar words inherited from a Latin word which will be similar so easier to understand. Our English Saxon habit of going up, picking up, etc is very strange to other cultures.
8. Avoid jokes, and clever comments. they do not translate well.