How do I change from consular processing to filing an I-485 after I-526 approval?

You are eligible to just file the I-485 here with proof of maintenance of status. The USCIS will request your file from NVC. You can also email NVC after your adjustment is on file that you are in the U.S. and adjusting status. Let us know if you need help with any or all of this.

You can file the I-485 with a copy of the approval notice and the USCIS will automatically pull the file. You can also notify NVC once you have filed and also once the case is approved.

Simply file the I-485. But be aware it will be at least a year, and possibly more than 2 years, before they adjudicate it. Depending on the COO, you may be better off filing a DS-260 as receipt of the CPR impacts the amount of time you are tied to the EB5 program, financially and immigration-wise.

My understanding is you need the form to transfer cases to the NVC, not from it, and an I-485 can be filed and you can request the NVC to end their processing.

You do not need to file Form I-824. That form is for when adjustment of status is initially selected, but afterward consular processing is desired. The I-824 is to request the USCIS, to notify the U.S. embassy or consular post in your home country of the approved petition and send them the file. Since you initially elected consular processing, but now wish to adjust your status, no Form I-824 is required; you simply file your I-485 with proof the I-526 petition approval as soon as an immigrant visa number is available. You must check the U.S. State Department''s monthly Visa Bulletin to see if your priority date (filing date) is current, i.e., an immigrant visa number is available.

You can simply file an I-485 if you are physically present in the U.S.