So then to amend my statement above, most skills you gain are at basic level from your origin path (unless stated otherwise) and those you get from your career path starting skills list are considered trained, and as drgabe said, if you gain a skill twice while creating it, you gain skill mastery ( +10%).
This is essentially correct. To clarify:
1) As to why all skills/talents from starting packages are included on the Rank 1 list:
As Graver discussed above the starting package skills/talents are listed w/ cost on the rank 1 chart in RT because when the Inquisitor's Handbook came out for Dark Heresy allowing homeworlds and background packages these sometimes changed the starting skill packages in ways that removed as well as added skills. As a result a character made in such a way would be crippled later when trying to get skills/talents for which the dropped skills/talents were prerequisites. As a result DH had to be errata'd to add those costs to the Rank 1 lists to fix the problem.
FFG didn't want to make the same mistake with RT so they made the lists complete to begin with.
2) Trained skills vs. Basic skills
Skills in the starting package are at trained. Skills bought with XP are at trained when bought. You do not have to buy basic skills separately.
However, while some skills are basic for everyone, others are only basic skills for individuals with a certain homeworld type, background package or origin path. So instead of the unwieldy basics over here/advanced over here DH approach, in RT they just added another check column to the sheet to help keep up with the basic skills in a simpler manner. Its a character sheet organizational change between the games not really a rules change.
3) Skill Mastery at character creation
In both DH and RT there is a paragraph on this. It does say if you get a skill twice you get the +10 mastery. However this refers ONLY to the circumstance at character creation where due to combination of homeworld, background, path, and career a character gets the same skill from 2 different sources. Then he gets to go ahead and start at +10. Otherwise he must wait until +10 becomes availible on his career advancement scheme (and if starting with +10, must wait until +20 comes up on the advance scheme to move up to +20). You cannot spend XP to buy the same skill twice to short circuit the mastery process.
4) Multiple purchases of Talents
For most skill and talent advances you may only take that particular advance only once. However, there are certain specific talents (i.e. Sound Constitution; Psychic Technique; et al.) that you may take more than once. The talents which may be taken multiple times state so specifically in the talent descriptions, and the limits on the number many times you may take the talents are stated in the career advance lists from which they are purchased. So UNLESS the talent description explicitly states otherwise, you may only take a talent ONCE.