It is "have been". It is basically never correct to say "am been", and it wouldn't mean what you want it to mean anyway.
One possible, correct sentence is:
I have been, for a short time, an employee of that company.
Or (this is more natural for me, but arguably less correct):
I have, for a short time, been an employee of that company.
Either way, it means the same. It says that you were employed a short time ago. It doesn't mean you're about to leave. I see why you might want "from" in this case, and not "for", but don't panic: in this case, "for" does not mean that it will only be "for a short time"! Just that it is "a short time" so far.
Now, you said you didn't want a grammatical or technical explanation, so we can stop there. But in case anyone else wants to know the grammar behind it, I'd like to elaborate a bit anyway.
A construction like "have been" is called the present perfect. It is for actions that are past and finished, at this moment. Its structure is have + past participle.
(There is also a past perfect, which is for actions that were already past and finished at some previous time. Its structure is had + past participle.)
A construction like "am being" is called the present continuous. It is for actions that are happening (right now), or that often happen (not necessarily right now, but before now and, we expect, after now too). Its structure is be + present participle.
But "to be" leads a complex existence. It is also used in ways that are basically unrelated to the present continuous.
A construction like "am been" is called the present passive. It is for actions where the subject ("I", in "I am been") is the recipient or target of the action. Its structure is be + past participle. You might say "I am insulted" (someone gave you an insult), or "I am seen" (someone saw you), or "I am blessed" (someone gave you a blessing).
It would be very unusual to say "I am been", though. That would mean someone was being you. If an English speaker really wanted to say that, they would almost certainly use different words.
There are a number of things going on in this question. Having read it over a couple of times together with the additional information in the OP’s comments, I think the best way to approach it is case-by-case.
First though it’s worth mentioning that while the OP has pointed out in a number of comments that the question is not about etiquette, it’s not that simple. When dealing with introductions there are established rules of etiquette that we have been trained to follow, whether we do that consciously or sub-consciously is not important, what is important is that they are there and that they do not always sit comfortably with other ‘normal’ usage.
…this is Tom Smith, our business partner; and this is Jim Blake, our lawyer.
First question – Can we do without the additional ‘this is’?
… this is Tom Smith— our business partner, and Jim Blake— our lawyer.
Generally yes. There are only two exceptions that I can think of; one comes later and the other is where a group is being presented and the person that they are being presented to, often a VIP of some type, makes a comment or asks a question after each name. Think of a royal reception where an elderly Royal makes a politically incorrect statement before moving on to the next embarrassed celebrity. In that case the introduction process resets and you would start again with a ‘This is’
In the same way that I turn to The OED for guidance on etymology and usage, for the definitive guide on matters of etiquette I head to Debrett’s:
Mary, this is Jim Wilson, Bob Aspinall and Sue Godstone.
As an aside, notice that Debrett’s is very keen that you should always make introductions two-way, completing the above example with “Everyone, this is Mary Brett”
Next, this vs these
OK, this is where it gets complicated.
The general rule is that you follow normal rules of grammar – this for individuals, these for groups
This is Mike from accounting
This is my neighbour, john Smith.
These are my classmates, Peter, Paul and Mary
You enter a minefield though when you start dealing with groups that can be thought of as a single entity:
and these are the other band members, Paul, George and Ringo
and this is the rest of the band: Paul, George and Ringo
Are both acceptable.
Finally we come to couples and here all the rules change, or rather, they fall apart.
Mary Bryant, a writer on weddings and general etiquette starts with the following:
Couples are introduced separately, although it is advisable to clarify the relationship (‘And this is Sarah, Peter’s wife/girlfriend’).
We’ve gone back to an additional ‘this is’….
However, it is also common practice to introduce a couple as a single entity - The reference found for ‘this is’ in Collins is correct in this instance
This is Mike and Sue Jones who live next door (A couple as a single entity)
Although….
These are our neighbours, Mike and Sue Jones (The same couple, now plural as neighbours)
I started off by saying that we can’t ignore etiquette and I stand by that. But etiquette, like dialect is only another form of usage, another set of rules – confusing and often contradictory.
Best Answer
Yes, it's perfectly fine English but is heavily nuanced.
"It would seem" expresses an opinion about the current state of something:
This is roughly equivalent to "I think we are out of milk". It also frequently implies the question of whether the situation is true, to which the listener could respond something like:
to mean they agree with the opinion. In addition, the expression is relatively polite since I have expressed my interpretation of the situation rather than saying it is definitively true.
Compare this:
to this:
I might know that you have no money, but by saying "it would seem" it sounds more considerate.
Lastly, the expression reflects the famous British characteristic of understatement in the face of bad news or adversity, to make the situation seem less dangerous or perilous than it actually is.
"Our situation is even worse than we had feared" is also fine. It says that the current situation -- implied by the "is" -- is worse than we previously thought it would be.
You are correct and the "had" is optional, but using it does imply that, at some previous point, they did seriously consider the situation.