Can I enter multiple Roth IRA conversions?

You can have multiple conversions as long as you have more than one Roth IRA entered. Each IRA or 401(k) that's converted must have a Roth IRA to go with it to convert to. [...]

Are living expenses in retirement pre-tax or post-tax with regards to income, dividends, and capital gains?

They are before income, capital gains, and dividend taxes. The program calculates these taxes for you, both for federal and state. So make sure you do not enter an expense for income taxes, capital gains, or dividend taxes. This would be double-counting. However, you do want to create an expense for property taxes or other local taxes that the program does not account [...]

Does the program allow for the change in the tax filing status if a couple was filing Joint and then one of them dies earlier than the other?

If one spouse passes away before the other, the tax brackets change to single status at that time in the [...]

Is cost basis used and can I enter the cost basis for investments?

Yes, the cost basis is used for tax calculations if you are projected to spend down principal for taxable accounts. If the account is linked, the cost basis updates every day automatically. If you manually enter an account, you can enter the cost basis as you see in the screenshot below. src="https://cdn.livehelpnow.net/clients/21145/kb/cbas1_8a21f1e8-d126-404d-b95a-43a0280e84d9.png" [...]

Can I run Roth Conversion scenarios to see if it makes sense and the best timing and amounts for a conversion?

You can run Roth Conversion scenarios under Scenarios>Roth IRA Conversion. Most people run scenarios where they specify that they want to stay under a certain tax bracket. The program will show you exactly how much to convert in each year so you just stay under the selected tax bracket. You can also choose your own amounts to convert each year by selected 'Manual Entry'. View the amount to [...]