Analysts and shareholders, uneasy about the multi-billion-dollar project, hoped Paris would be a turning point.
The 100-150 seat C-Series is two years late and over-budget.
Mr Cromer played down the show's importance for C-Series announcements, saying it provided brand "momentum".
Bombardier, which has a big operation in Belfast, has seen rivals unveil a series of deals in the show's first two days.
Mr Cromer was appointed as part of a wider management shake-up at the Canadian company, and the planemaker has a big presence at Paris show.
Cost overruns pushed Bombardier into a loss last year, its first in almost a decade.
The company has 243 firm orders for the C-Series - the biggest from Lufthansa's Swiss International - and wants to have 300 by the time it enters service in the middle of next year.
"I think we feel pretty good about being able to achieve that, and potentially beating that target," Mr Cromer said. "The momentum is very tangible right now, and our job is to turn that momentum into sales."
He said: "The focus on air shows (for orders) is in some ways unnecessary. Sales is a 365-day job. We will announce deals at the appropriate time."
But a lack of order news, even small ones, in the last two days - traditionally when planemakers tout their biggest deals - will concern analysts.
In April, Rolland Vincent, a former Bombardier director, told Canada's Financial Post that without any "blockbuster" orders at Paris, the show "will be a really dark week for them".
Analysts have urged Bombardier to be more aggressive on price and offer bigger discounts in order to book more orders quickly.
But this strategy could further strain relations with some big shareholders, already concerned about mounting development costs, which have reached about $5.5bn - more than $1bn above initial forecasts.
Mr Cromer does not seem in any hurry to cut costs for a bigger market share, however.
"Everyone wants to get into the price discussion and say that if you don't cut prices you won't get orders. The fact of the matter is, this is an all-new aircraft that fits into many different airline business plans. Price is just one of the aspects during negotiations," he said.
New Bombardier president Fred Cromer says the planemaker is still set to meet sales targets for its key C-Series aircraft, despite so far failing to announce orders at the Paris Air Show.