Someone misrepresented my work in a published paper
While nothing much may come of it, I think you should write them pointing out that they have missed some things about your work. Ask them for a correction, though don't expect one to occur. If you want to smooth the waters, congratulate them, also, for the good things they have done in their own work. 

But letting it lie without comment serves no one well and might lead to a repeat in the future. 

If you want to be a bit more aggressive, copy the conference chair on your email, but think hard about the consequences of that. 

I'll assume that the errors were unintentional, in which case you should expect a good result.