Struggling with looking up a value

Hi all,

I have the following report:

Entries, Durations, Orders and Products are all tables that I use in this report. You can also find them at the bottom of this post. In addition, I have a dax-generated calendar.

What I'd like to achieve is a stacked bar chart where I can mark all 'products' that have valid 'entries' with the 'best' corresponding category from 'orders'. By 'best corresponding category', I mean the category that belongs to a valid duration, and if there are multiple valid durations, pick the one that has the earliest start date. In this case it would look somewhat like the bar chart in the screenshot above but then: 3 ID's:

229 -> Coloured with Category 'Unknown'

288 -> Coloured with Category 'B'

973 -> Coloured with Category 'A'

'Final result' is where I get stuck for now. Let me break it down for you:

For every Products[ID] and selected Calendar[Date], I check if..

..they have a Duration using:

have a duration = 
CALCULATE (
    COUNT( Products[ID] );
    FILTER (
        Durations;
        Durations[Start] <= MAX ( 'calendar'[Date] )
            && Durations[End] >= MIN ( 'calendar'[Date] )
            && Durations[Start] <> BLANK ()
    )
)

..they have an Entry using:

have an entry = 
CALCULATE (
    COUNT ( Entries[ID] );
    FILTER (
        Entries;
        Entries[In] <= MAX ( 'calendar'[Date] )
            && (
                Entries[Out] >= MIN ( 'calendar'[Date] )
                    || Entries[Out] = BLANK ()
            )
    )
)

..what the minimum Start-date/time is for all 'valid' Durations using:

minstart = CALCULATE (
        MIN ( Durations[Start] );
        FILTER (
        Durations;
        Durations[Start] <= MAX ( 'calendar'[Date] )
            && Durations[End] >= MIN ( 'calendar'[Date] )
            && Durations[Start] <> BLANK ()
    ))

Now I want a last column that will return the corresponding Orders[Category] for the given Products[ID] and 'minstart'. I tried using:

return category = 
VAR minstart =
    CALCULATE (
        MIN ( Durations[Start] );
        FILTER (
        Durations;
        Durations[Start] <= MAX ( 'calendar'[Date] )
            && Durations[End] >= MIN ( 'calendar'[Date] )
            && Durations[Start] <> BLANK ()
    ))
RETURN
    LOOKUPVALUE(
        Orders[Category];
        Orders[ID]; MAX (Products[ID]);
        Durations[Start]; minstart
    )

But I get:

Any idea what's going wrong? I'm struggling to understand what's happening within the LOOKUPVALUE part of the 'return category' measure.

Your help is very much appreciated. If someone cares to explain how I can upload a pbix-file in this post, I will be happy to do that.

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Additional information:

Orders:

Durations:

Entries:

Products: