It was heading directly for them but was making slower progress than theirs.

But many other English learners here are making slower progress.

"They'll make slower progress with most of their animals gone."

The reason he gives for open access making slower progress than initially though were:

He made somewhat slower progress than his shovel-equipped rival next door.

The land is difficult for horses, and we made slower progress.

They also want slower progress toward creating a single European currency.

An early start will thus mean slower progress and hence more time to consider the consequences.

However, he had made slower progress than he had hoped.

This allows for real time playing while everyone is online and active, or slower progress if not.