Speaking after the 3-2 defeat, Mwaura said the club’s new arrivals have shown that they can deliver for the club when they eventually settle.
Mwaura was overseeing the Millers' Kenyan Premier League (KPL) clash after the club changed its coaching personnel shortly before the match.
Kenya U-17 assistant coach Godfrey Oduor was appointed earlier on Wednesday, but could not take the reigns immediately and followed the proceedings from the stands.
Of the new arrivals, Austine Ochieng was the only player who faced the Slum Boys in KPL match week 24. Ochieng came on in the second half to replace Dennis Wanjala.
Leonard Kasambeli, Paul Kibande, James Kibande, and Hastil Wekesa are the other players signed by the club.
“I was particularly impressed by the new signings. Generally, the new boys have shown positive aspects and I hope they will be able to help the club going forward," Mwaura told Goal after the match.
"We had a good game against Mathare United, that was a good performance but unfortunately, we failed to win.
“We need our fans to turn up in our next game and I promise them the club is ready to reward them with a good performance at home then."
Nzoia Sugar will host Western Stima on April 24 at Sudi Stadium and will be eager to return to winning ways in that match.
Western Stima have been struggling of late, claiming only two points in their last five games, and were beaten 2-0 at home by Ulinzi Stars in their previous match.