looking pretty good to me, with a comment on the $1 below
for the question about year-end balance for IRA you would literally give your 12/31 balance in your IRA(s) - note this is considered across all IRA account not just the account where the Backdoor Roth is happening, if you have other accounts but hopefully not the case as it complicates the backdoor Roth process if you have IRAs with pre-tax earnings.
since you did the 5k Roth conversion in 2025 I assume your cleared out the account and it was indeed $0 at year-end. Then you backdated the 7k conversion into 2025 but that was done after 12/31. The 8606 is structured to handle all the backdated situation so you literally follow the instructions and provide the MV as of 12/31/25 based on your year-end brokerage statements.
on your basis carryover it shows "5001" - just to be accurate tho, if you did a 5000 contribution and there was $1 earnings before the conversion so your Roth conversion was 5001 (a normal situation and correct to clear out the account to zero) - then your contribution is still 5000 and conversion is 5001, you should end up with 5000 of the conversion being tax free and pay tax on $1. That would make line 14 $7000 here and line 18 $1.
you didn't show line 8 but I assume you have 5001 there.
