Deviations from the Published Core Rules
While we love the published Space:1889 materials, there are several elements which will differ from the published content during this campaign.
Position of Women
In the original GDW rulebook, a number of careers were specified as "male-only." In the recent Clockwerk version, while the rules don't enforce those kinds of limitations on female characters, in text, female characters, upper-class in particular, are described with very limited options.
This doesn't sound very fun to play in the context of a campaign, so within the Shifting Sands universe, we've chosen the following background:
In general, in Britain any career is open to women characters. In 1872 in our timeline, at the urging of Queen Victoria, Parliament passed a series of laws with the following effects throughout the Empire: a) women gained the right to vote, b) all universities opened all fields of study to women, and c) the military was charged with creating female-only units (such as regiments, naval vessels, aether flyers, etc.). That doesn't mean that there aren't still British men (and ladies!) who strongly believe in traditional gender roles.
However, other Earth nationalities (such as France or Russia) and cultures, religions, social groups, etc., still limit women in general from various careers and responsibilities. Most Martian cultures, though, have millennia of equality.
What this means to players: female characters are not restricted from any given career, no matter the position of their government on women's equality. To develop a character from a nation which still limits women, we will ask for a backstory explaining how the character found her way into her career.
The North did in fact win the American Civil War
Some of the most recent Space:1889 material changed American history such that North America in 1889 both the United States of America and the Confederate States of America exist. We feel this would take focus away from the story we want to tell in Shifting Sands, so in the campaign universe, American history up to 1870 is unchanged from the timeline as we know it, which can be summed up as: the North won the War Between the States.
Details of the Solar System
If you weren't already a fan of the Space:1889 setting, you may be surprised by how many books have been produced, first by GDW, then Pinnacle and now Clockwerk. There is a vast amount of published detail on the inner planets of the solar system: as one example, for Mars, there are great amounts of detail about its geography, thousands of years of history, the cultures and social organization of the sentient races, animal species, etc.
We are not limiting the Shifting Sands universe to precisely match all the details about the solar system to those given in the previously published materials.
So, this means that while you are welcome to study any and all Space:1889 materials, please bear in mind that you are likely to encounter details which aren't true or accurate in the Shifting Sands universe.