I can't tell you if your current server framework will work. Before you decide on MRSS or JSON, you should understand the advantages/disadvantages of each one. You should read the Roku specs for each feed type to determine which one is appropriate for you. For example, if you plan to monetize your channel, you should use JSON. These are the types of questions you need to ask yourself.
If you are interested in my software, you should take a look at the demos and tutorial videos before deciding what product is best for you. Make sure you understand the requirements of each product.
Windows desktop software for creating BIF
(Trick Play), Direct Publisher
(MRSS, JSON), and FireTV
feeds @ GitHub/rrirower
. No programming knowledge required