Do not delete iTunes and start again. Although this is a common practice on phones, it is a very bad idea on your computer. It is long-winded and unnecessary.
Keefykins wrote:
I then went back to the 'recently added' section and noticed a blue circle with 3 white spots
I cannot recall exactly what the "not downloaded" icon looks like (since I never have that issue), but that sounds as though the songs are not downloaded to your computer; did you buy them from the iTunes Store, or are you using the cloud service?) If they are not downloaded to your computer, then that's why they're not in the My Top Rated Playlist. Right-click one of the specific problem songs and if there an option to download it, use it.
Something I realise that I was not clear enough about is how Smart Playlists work:
you (and I mean you as the user) cannot add a song to a Smart Playlist by using the right-click/add to Playlist option. The ONLY way for a song to be added to a Smart Playlist is if the song meets the rules of the Playlist. This also means that when you click on Add to Playlist, only the Regular Playlists are shown. See the screenshots below (which I've trimmed in order to have less clutter):

- in the screenshot above, which shows the Add to Playlist options (1.), the only Playlists shown are Regular Playlists (2.)
- the Playlist Folders that you can see (2.) are simply where those regular playlists are located. You cannot add any song directly to a Playlist Folder
- no Smart Playlists are shown (2.) because the user cannot manually add songs to them
However, (using the same song) if I go further down the pop-up menu, to Show in Playlist (3.), we see the screenshot below:

- I have erased the other Playlists, for clarity, but they are there
- notice the My Top Rated, no play, 5.5 months one. It has the Smart Playlist icon that I mentioned in my previous post. At the bottom of the playlist panel you will notice the Regular Playlist icon as well. This means that this specific song is in every one of the playlists indicated. That is 15 Smart Playlists and three Regular Playlists
- the My Top Rated is one of those Playlists. Note that I renamed my version of this Playlist, but don't let that concern you, it's not relevant to our discussion
To be clear, you, as the user, cannot manually add any song to a Smart Playlist, either by using Add to Playlist or by dragging/dropping it in. You can however, cause it to be added to a Smart Playlist by:
- giving the song an attribute that will cause it to be added to that Playlist. In the case of the My Top Rated Playlist, this means assigning a four or a five star rating to the song. But the song will need to be downloaded and playable in iTunes, on your computer
- changing the rules of the specific Smart Playlist. Note: do not change the rules to your My Top Rated Playlist. It is not the way to sort out your specific issue and doing so will produce unintended results
So:
- confirm that your songs are downloaded to, and playable in, your iTunes
- confirm that the songs have either a four or a five star rating
- once they meet the two points above, either look in the My Top Rated Playlist to confirm that they are all there or use right-click/Show In Playlist on individual songs to confirm that that specific one is in the My Top Rated Playlist
You can confirm that the My Top Rated Playlist is working correctly by giving a known good song a four or five star rating. Doing so will cause it to go into the Playlist. Changing the rating back to its previous status will remove it again. In the unlikely event that it is not working correctly, we can look at that too.
Let us know how you're getting on, although note that it may take a while before I personally respond. (Retired, but pressure of social life, other commitments and sleep to be had are my current excuses.)
Retired, but with a sense of humour (yes, a British sense of humour).