Using a "hyperlink" effect in Winforms applications

Not even browsers work this way. Use a LinkLabel, not a TextBox.

In general, it’s a good idea to use hyperlinks (real or simulated) in thick-client apps for opening forms of additional information. It is helpful to distinguish between a control that merely navigates (a hyperlink) and a command that changes the underlying data (a command button), so the users know what they’re getting into. I don't think most users care (or even know) if a browser is involved or not. Navigating is navigating.

Making an attribute value look and act like a hyperlink like you’ve done is fine except for one thing that is a showstopper for most applications: it precludes any other interaction with the attribute. The user can’t edit or even copy the attribute value since any clicking in the field will launch the new form. Keep in mind that to edit a value, such as to correct a day of the month, the user may be inclined to click in the middle of the field to position the cursor. Even if you’re using a drop-down menu (e.g., to set the organization), you want to allow users to click in the field and select by typing the first few letters of the value they want. If your app has one drill-down-able field that needs to be editable, then for internal consistency none of your fields can use hyperlinks –all drilldown needs to be by some other method.

Also, while hyperlinks are intuitive for navigating, such as drill-down, I’m not so sure they’re good for assigning a field value. There is a difference between getting more information about Acme Corp organization (which is what your Acme Corp link implies) and getting a dialog to pick the organization for John Smith (an assignment function). So if your intent is assignment rather than true drill-down, then links are probably not a good idea. For assignment, the button with the three dots makes a lot of sense. Assignment changes the underlying data, so it should use a command button. It’s a natural extension of the button in a dropdown control. The three-dot button caption minimizes the space used and is associated with dialogs since that’s what they imply in menu and button captions. It might look old-fashioned, but that’s why it works –it’s consistent with past user experiences.

Looks okay to me. The concept of links has anyway already migrated from web to desktop applications. Users should accept this without problems (maybe after first ten minutes playing out with your program).

Also quite popular in enterprise applications.

Maybe consider changing the color, to, maybe brown or green, so that it doesn't immediately imply a native web link.

Also many web applications built with some event-driven frameworks (like ASP.NET WebForms, JSF etc.) heavily use links that do not link anywhere but invoke some server-side processing (basically an event handler). So it's not unusual use.