How can I refile an I-485 application?

This is a normal routine, you cannot have more than one conditional green card at the same time. Unless you no longer have a valid green card, you may not be able to successfully apply for a second green card.

While your conditional green card is still valid/active, you will not be able to file an I-485 application. You will first need to withdraw your application for permanent residence based on the EB-5 petition before you can file for another I-485 based on a different immigrant petition.

If the I-485 is based on an EB-2, you can only be out of status for up to 180 days, but to file under EB-5, you can not be out of status even one day. There is no restriction on filing a new I-485 but you need to make sure that new I-485 meets section 245 eligibility criteria. I-485 is an application to adjust from nonimmigrant to immigrant status and not for changing from one immigrant status to another. It is often best to prove the second case abroad so you can surrender your conditional status and then apply for a new green card abroad.

You can file the second I-485 and then withdraw the conditional green card at the I-485 interview. Disclose at time of filing I-485 as well.

Based on the information provided here, a refile would lead to the same result - a denial. By definition, a resident cannot file for adjustment of status. You should consult with an attorney in order to properly terminate your conditional permanent residency (CPR) status and follow USCIS guidance on how to handle adjustments when CPR is terminated.

There is no time limit to file to adjust. But there are requirements for adjustment of status, such as being invalid, nonimmigrant status in the U.S. You may wish instead to consular process for the immigrant visa.

There is no specific waiting period to refile an I-485, but keep in mind that conditional lawful permanent residents may not adjust status in the United States. You should seek the advice of experienced immigration counsel to see if you should (1) request termination of your conditional green card status first and then refile the I-485 or (2) apply for immigrant visa processing at the U.S. embassy or consulate in your home country.

You can not as long as you have a green card. You would have to give up the conditional status first.