French: pas - steps
Bambara: pa(s) nu - little dance steps
The ‘nu’ in question… I have been told it means ‘our little love together’. However, I could not find ‘nu’ in a dictionary format.
examples:
i ka pas nu bɛ ne lafiya
n minɛ an ka pas nu bɔ ɲɔgɔn fɛ
n ye n miiri an ka su fɛ kuma nu na
ka miiri an ka su fɛ jate nu na
ka miiri an ka su fɛ lovou nu ma
Is the nu here in question not actually the demonstrative ninnu or nunu which means ‘these/those’? It frequently is very truncated into something that sounds just like “-nu”:
Pas ninnu [pas nu]
‘Those/these steps’(Pas being a French loanword for ‘step(s)’)
So, the example “I ka pas nu bɛ ne lafiya” would mean 'Those/these steps of yours put me at ease".
Looking at your above examples, I think that all of those “nu” words are actually the demonstrative, but out of context, I can’t be sure.
Coleman! Your above interpretation might be correct. I will reply again once I have feed back because I’m wondering if the nu is a slang spin on peu… ?
Coleman, nu is still being explained as meaning little. Like fitinin… dɔɔnin… but in plural form: ninnu / ninw.
N y’a ta yɔrɔ min na, n y’a bila yen.
Thoughts?
The plural forms that you are giving are the same ones that I was “hearing” when you gave your original examples, so I think that the literal interpretation of ninnu/ninw as the demonstrative (“these/those”) still can hold.
That said, your teacher/friend/interlocutor might be referring to or thinking that the proper interpretation (of at least some of the examples) is in fact with the diminutive suffix -nin (equivalent to ‘wee’ or ‘little’ in English, but it gets tacked onto the end of a word; it is the counterpart of -ba).
In this case, one of your examples could be the following (I’m going to put in dashes for clarity’s sake since in this case, “sufɛkumaninw” would actually be one word tonally):
N ye n miiri an ka su-fɛ-kuma-nin-w na
‘I thought of our little words of the night’
(Note that sufɛkumaninw could likely be pronounced more like [sufɛkumaninnu], but I am not writing it here since -lu/-nu isn’t normally considered “standard” Latin-based Bambara orthography. It does show up in dictionaries though and in N’ko orthography, -lu/nu is actually the standard.)
Tonally there would normally be a clear difference between this:
Kuma ninnu
‘Those words’
And this:
Kumaninw (or, kumaninnu)
‘little words’
In Latin-based Bambara, there isn’t a standard way of marking this, but the short of it is -nin is a suffix without its own tone (it gets determined by the word it attaches to), whereas nin (‘this/that’) is a low tone word. So, simplifying things (since tone marking is complicated and can quickly involve various theories and assumptions of what is the underlying tone vs the surface realization that one hears), we can “see” the difference like this (an acute accent like this one <é> means high tone and a grave accent like this <è> means low tone) :
Kúma nìnnu
‘These words’
Versus:
Kúmaninnu
All that to say that -nin does indeed mean “small” just like dɔɔnin or fitinin and it can carry the plural marker (ninw or ninnu). And when plural and spoken at a decent pace, one might hear it is [nu]. 
But the question of whether that’s the right interpretation (instead of the demonstrative nin) for a particular sentence is another matter! 
In that case, comparing how someone pronounces the tones of the sentence could be helpful.
All meanings, we know, depend on the key of interpretation. ~ George Eliot
Thanks for your linguistic expertise on the matter Coleman! I love how you explain things. Squad goals!! 