Flames of Phlegethos upcasting spells

I am trying to get Flames of Phlegethos to work with upcasting spells. My DM and I have figured out how to get it to work at the base level of a spell (adding "ro<1" to the end of the damage roll) but we cannot figure out how to get it to work when casting at a higher level. We were using Burning Hands as the test subject. Any help is appreciated as I have not been able to find anything that solves this.    

You can disable the native Higher Level Casting inquiry and set your own through the normal damage field. To disable the native query, take out the 1 before the d6 in the Higher Lvl Cast Dmg line. Then remove all the text from the "At Higher Levels" box. Next, in the damage field put in the following [[?{Cast at what level?|1|2|3|4|5|6|7|8|9}+2]]d6ro<1 That will ask you for the spell level, calculate higher castings appropriately, and reroll 1s one time as per the feat.

That did it! Thanks a bunch!

Is it possible to modify your formula to work with chromatic orb when it's doing fire damage? I've currently got the damage set as 3d8 (for a level 1 spell) and damage type set as "?{Damage?|Acid|Cold|Fire|Lightning|Poison|Thunder}" so I don't know if there's a way to call the "ro<1" when I select fire damage. If not, making another line for fire damage specifically would be pretty simple.

The best option would be to make a new entry just for fire damage. There are ways to make macros that would work like that, but it would be a lot more complicated, and not compatible with the regular spell entries.

I figured that would be the case. Thanks for your help :)