1) I put some assets into AssetFix.csv
2) I deleted all fields except for "Name" for those assets
3) I connected to IB paper trading account with the Download script
4) I set it to "All Assets" and double clicked on "Save Assets To"
From this we get:



The resulting file filled all fields, assumingly from the broker info. However, it has the following weird properties:

- it refers to STOOQ for historical data, which is kind of weird of IB to do, right? (Maybe it was Zorro and not IB who filled this out?)
- Despite the Price being different for each asset, the MarginCost is always 12.5, which would be true only if all prices were 50 if Leverage is truly 4, right?

What is going on? How to be sure that the data loaded really reflects IB parameters? Should I adjust some of it by hand?

Now I'm getting "asset not subscribed" error.
A quick try online suggests that paper trading accounts cannot subscribe to price feeds.
So this means, as long as I'm paper trading the whole process will have to happen "blindly" with IB?
Or am I wrong about this?

Assuming you have a live trading account with IB, you will need to "subscribe" and pay for the data coming from exchanges.
FX and Index CFDs are free and do not require a explicit subscription; but an account has to have a "permission" for them.
Check appropriate settings in Account Management.

I see, thanks for the info!
I presume one can still buy and sell an asset even if one is not subscribed to its feed, right?

Yes.