The team has debuted a significant package of bodywork and suspension changes that were supposed to have run for the first time at the cancelled Imola event last weekend.
Despite the obvious complications inherent in learning about a new package on a tricky street track, the team opted to keep them on the car and put some miles on them.
Lewis Hamilton finished FP2 in sixth place while his team-mate George Russell was 12th.
"It's difficult with Monaco, really difficult to judge," Wolff told Motorsport.com when asked about the upgrades.
"But at least we haven't seen any behaviour of the car that would have been deemed as really negative."
Asked if the car was giving the drivers the confidence they require, he said: "I've never heard a driver saying in Monaco that feels good!
"I think it's always on the knife's edge. You've seen that with [Carlos] Sainz. And therefore not lots of great praise, but definitely going in the right direction."
Wolff stressed that he was proud of the effort made by the team to get the new parts to the track.
"Massive," he said. "You see the whole bodywork is different, front suspension, the floor is different.
"A mega job of everybody in Brackley to have delivered that, and now this is our new baseline and we have to work from here."
Wolff also noted that after a disappointing FP1 session, Red Bull made progress in the second session, and reckons Max Verstappen showed he is a step ahead of the rest of the field.
"Max was in his own class on the long run. I think we're pretty close together on a single lap, at least today, but in the long run you see a car that has performance and has no degradation. They've done a good job."
Despite being only sixth on headline times, Hamilton insisted that it had been a positive first day with the new package.
"I've generally had an amazing day, I really enjoyed driving today," said the former world champion.
"I want to say a big, big thank you to everyone back to the factory, because to build and design and develop a car is not an easy thing. And everyone's put so much time in, so many hours of hard work to have us here today.
"I'm glad that we were able to keep it on track for them. And I think we got a lot of data. I mean, it's not the place to ultimately test and upgrade but the car was generally feeling good.
"It was a bit of a shame, we weren't as close as I'd hoped at the end of the session, but definitely felt the improvements. And we've just got to keep chipping away to see if we can squeeze any more juice out of the car."
Asked if there was a specific area of improvement, Hamilton said: "There is, but I'm not going to say where. There is an area, and it's very clear where the lack is lack of performances for me.
"And so we'll talk about that in the debrief. We'll put our heads together and try and figure out how we can do that within what we have. And but hopefully this gives us a platform to build on moving forwards."
Russell was also upbeat about the improvement to the car.
"There's definitely some positive signs to take from the session, definitely improved from FP1," he said. "It's never easy around this place.
"We've made a lot of changes, things we would have done on the previous iteration of the car, as well.
"It's not anything unique at all to these new updates. And we'll work overnight to see what more we can do to try and get more out of the tyre.
"We know that the base performance of the car is good. And we normally overachieve maybe on a Sunday and underachieve on a Saturday. So we need to try and flip those over this weekend."