You might refer to the notes here, here, here and here for information in divorce, court orders and property. I would advise you to see a family tax lawyer to discuss your options as this is a complex are of tax.
If you were in a situation where you lived in a rented property as opposed to the studio flat which you part own, you could tranfer your share of the family home to your ex-wife on the basis that she will continue to live there. You could then make a joint election under Section 225B TCGA 1992 whereby you would be treated as having continued to live in the family home until the earlier of the date of the transfer and the date the property is no longer your ex-wife's main home. That would effectively exempt from CGT that part of your share of the "paper gain" (arising from you being treated as effectively selling your ex-wife your share of the property at the opee market value) which is not covered by your occupation of the property and the last 18 months of your having an interest in it. Given that you only moved out in October 2014, only about 6 months of your "gain" would be liable to CGT with the first £11,100 being tax free due to the annual CGT exemption.
However, the problem is that such an election would expose a larger part of the gain you will make on the sale of the studio flat to CGT as you cannot have more than one main residence at any one time.
If your wife gives up her share of the studio flat to you, then that will be a disposal for CGT purposes and she will have CGT to pay on all of her share of the "paper gain" as it has never been her main home (£47,500/2 = £23,500 less the £11,100 annual CGt exemption) as she has never lived there.
There is another possibility. Section 248E TCGA 1992 (link 4 above) allows two people with joint ownership of more than one property to exhange their respective interests so that they each end up with one property. The exchange may need to include a with no immediate CGT implications. However, any equalisation payment required to balance the exchange could give rise to CGT and stamp duty.
If no elections are made, you may have cGT to pay on part of the "paper gain" you will be deenmed to have made when giving up your share of the family home but you get the last 18 months of ownership as a tax free period where the proeprty has been your main home. 18 months back from now covers you back to April 2015 and exposes the gain for the period from November 2014 to March 2015 to CGT.
You would be exposed to CGT on all but 18 months worth of the studio gain but you would have acquired half of it from your ex-wife at the market value of her share, say £95,000 which would reduce your gain on sale as your CGT cost would have increased to £166,500 (£71,500 + £95,000). Your wife would be exposed to CGT on her share of the studio gain as described above (£190,000/ 2 - £71,500 - £11,100 x 18% or 28%). In eefect, you would both have £23,500 gains but the amount of yours which would be subject to CGT would be reduced proportionately by the period that you occupied it as your main home. As a 40% taxpayer, you would pay CGT at 28%.
I hope this helps but let me know if you have any further questions.