In my experience, most dogs are not going to master the weave poles by working on them once a week in class. Especially since you are experiencing problems with them, I think this is something that you MUST practice at home.
I live in an apartment and I can't leave equipment outside. That means that my weave poles live in my living room. I built a set of six (with my dad's help!) and they fit with just enough room to allow for an entry & exit, although we can't work on difficult entries very easily due to lack of room.
I used to work Luke through the poles every single day. I used a very high value treat and/or reward (like tug). The sessions were very brief (five minutes or so) but EVERY day. He had his weaves by the end of our beginners class thanks to this (the poles got built between the first and second week of classes).
If space is a big concern, just build a set of three. It sounds like your entrances are the big buggaboo, so a short set of three should allow you to work on this easily. You might consider purchasing a set of guide wires for your home set to ensure that Zoe always gets the correct entrance, then start weaning them away.
If this is absolutely not a possibility, the only other suggestion that I have for you is to get to your training club a few times a week to practice. Weaves need TIME and PRACTICE. They will come with no other method.

Luke -- Lab/Shepherd (1-1-04) Open Versatility, EAC, EJC, TN-E, TG-E, HP-O
Kaiser -- Alaskan Klee Kai (12-30-07) Future Agility Star!