Ahh, bit clearer now..
A few points which may help you, just been through this myself. FYI I chose to get the faa private and faa med despite holding a 61.75.
Firstly, have a look at CFR61.123, you need to have a private certificate as an eligibilty requirement for the cpl. It says a private certificate issued under this part, ie part 61. That sounds like a 61.75 would count but only your dpe or fsdo can tell you the definitive answer to that. The dpe is the one who signs off your cpl application before you fly the checkride with them. They will not allow you to progress to the flight if they dont like the paperwork. Strongly recommend you work out who will be your dpe for your cpl checkride and ask them before you go much further with this and I would be interested to know the answer myself. My guess is that it does count but the dpe will be unsure and have to put in some calls to their fsdo to satisfy themselves which may take time. If they say it doesnt count you will have to meet the private experience requirements and take a private checkride and knowledge test and have an actual faa med, all in order to get a faa private first. That also means a separate TSA application to the IR and ME, making three in total but you need three anyway as the cpl would be your initial faa licence so no big deal there.
You should clear this issue up before worrying about the 61.75, because whilst your preexisting ppl training will be accepted towards the requirements if you need a private cett there are things such as 100nm dual night crosscountry you will need that you probably dont have. If you have to do the faa private the 61.75 is unnecessary although helpful as you wont then need student solo endorsements if you need solo hours. You just need to ask the faa med examiner to use the version of the certificate that has the student licence on the back of it and you could do it that way.
The 61.75 will give you ppl privledges, and your caa med,when verified, will work for that purpose. You will need a bfr right away, that is required to be considered current in your situation but your 61.75 plus caa med would then work for any solo time you need, and your medical status is irrelevant for the dual portion.
The gotcha is that you will need a faa medical for the flight test anyway (cfr61.23) as an entry requirement and it looks pretty clear that means a faa class 2, your verified caa class 2 is only the equivalent of faa class 3 regardless of whether the dpe would accept it so either way you will need to get a standalone faa class 2 (or 1) by that time. You can do that here or there and it has no effect on your existing verification process.
When it is issued, the faa will fax your verification letter to the fsdo you nominate on the form and to you on the fax number you give them on the form. I had one back in three weeks and another took a month. Its worth a call after three weeks, mine was stuck because faa claimed uk caa hadnt responded and uk caa denied they had been asked, but was sorted then within a week, arrived xmas eve. You then take the verification letter and suporting docs to the fsdo you nominated (usually requires appointment) or a dpe from that fsdo who is a foreign pilot examiner, and you will receive the temp 61.75 with the real one following in the post.
Hope this is what you are after, and do let us know if a 61.75 suffices for entry to the cpl checkride if you find out, Im sure plenty of other people are in that situation.