What do mean by correctness? It's a made-up word; it can't be right or wrong. You would need to word the question to explicitly define what answers you expect.
You could ask whether your portmanteau word conjures its two constituents in the reader's mind [note that it's the reader's mind; most people — and certainly everyone here — will first encounter the word in writing].
You could ask whether your proposed pronunciation is reasonable. Since no-one will have heard the word before, they will have to imagine how it sounds for themselves. Ask whether their idea matches yours (which is implied in your question here, but make that explicit). Ask whether there are any rules which govern how your word might be pronounced.
You don't need to give much in the way of background. Questions about computer names tend to get stamped on, so don't make it quite so obvious. Concentrate on the English surrounding it.
How do I create a successful portmanteau word?
I've written a simple, native development framework, and as a name for it I've coined the portmanteau word simpletive.
Does simpletive conjure the two words I used to create it? (There's a clue in the first sentence.) If it doesn't, are there any rules which would help do so?
I would like that to be pronounced /'simpəlˌtiv/. Is that how you pronounced it to yourself, and if not, are there any rules which govern pronunciation of unfamiliar words?
It's not generally a good idea to have more than one question mentioned per post; but here you are asking about the mechanics of creating your word, and providing an example which should guide the answer about recognisability. You may find that someone answers one half and provides a link to an answer about the other half. That's fine, because your question is still a general pointer which joins things together.
By making the question general, How do I do this?, and not the specific Is this any good?, your question may be of use to others. This is a fundamental principle of SE questions. (You know that already; you're asking here! But I mention it so that this answer may be useful to others.)
Now that you have a sufficiently general, but ultimately helpful, question, make sure that no-one has asked something similar before. In this case, the automated suggestion system doesn't find one, so you may be OK.