It only takes a few minutes at most, once you are accustomed to the procedure. I should note that I personally do not do the cron step, which automatically updates the executable and ini file at regular intervals. I prefer to update the files manually if/when needed.
Unfortunately, I don't use any immediate messaging software, as I find it distracts me from my regular work, so I would be unable to help you using this method.
However, if you encounter any problems, I am sure we can sort them out here in the forum. There have been a few threads recently where people have attempted this procedure and run into problems (usually by missing a step or two) and, after a debugging process, we have succesfully got them up and working.
I must admit, I have never had a reason to change the temp directory, so I am not familiar with the procedure, but I am sure someone else here on the forum will have some experience in this regard and will be able to help.
I think it is probably best if you concentrate on a working local install of PHP first, then worry about the required ini file changes after that has been achieved.
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