Caretaker manager Millen will again take charge for Thursday's clash at Villa Park following the sacking of Neil Warnock, with Newcastle United boss Alan Pardew in talks over a switch to Selhurst Park.
With compensation agreed between Palace and Newcastle, the formalities of Pardew's move have yet to be completed.
Millen, meanwhile, has been impressed with the squad's attitude since Warnock's departure and hopes Sunday's battling 0-0 draw with QPR can be built upon with a positive result in the Midlands.
Palace were beaten 1-0 in the reverse fixture earlier this month - Christian Benteke grabbing the winner for Villa - but Millen also feels positives can be drawn from their display in that defeat.
"We will continue to get on with our job and prepare for Aston Villa - the reaction we got at QPR was exactly what I was after," said Millen, who will again be without Marouane Chamakh (hamstring).
"I enjoy working with this group of players. You could see that the lads pulled together and worked really hard for each other.
"The players see [the speculation] and have their usual banter. They have coped unbelievably well.
"They are a really resilient group and we will be ready for the Villa game - whoever is in charge.
"We played well against Villa earlier this season and we'll take confidence from that and will go there looking for a result."
While Villa have been somewhat out of sorts of late, they are unbeaten in four home games.
Paul Lambert's side rounded off 2014 with a drab 0-0 draw against Sunderland, but the manager took heart from his side's performance.
Lambert, without the suspended Fabian Delph, expects Palace to pose a threat regardless of who is in charge on Thursday.
"Whether Keith gets it or someone else comes in and takes it, remains to be seen, but they're the same group of lads that we played against a few weeks ago," he explained.
"We know it'll be a hard game but we're playing well and passing the ball really well.
"All we need to do is finish our good play off and let's see what happens.
"[The point against Sunderland] was a good point, it was a tough game, but we're at home. We just have to open teams up and try get that goal.
"It'll be a hard game, whether a new manager comes in or it's Keith."
